JP3512168B2 - Signal transceiver - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for transmitting and receiving signals between devices or chips, and more particularly, by using a cable or a flexible substrate, between devices or between different boards in the device or on the board. It is suitable for signal transmission / reception devices that require stable transmission / reception of data even when the power supply voltage or the ground potential is different between the transmission / reception devices when transmitting / receiving signals between mounted devices such as LSI and IC. is there.

[0002]

2. Description of the Related Art In conventional signal transmission / reception, for example, in the case of differential transmission, as in a signal transmission / reception apparatus 1000 shown in FIG. 9A, a receiving device 130 is provided in order to prevent waveform disturbance such as reflection due to impedance matching of a transmission line. A bias resistance circuit 102 that provides a terminating resistor 105 to short-circuit the differential line pair 103A and 103C, which is a data line, and further determines the intermediate potential of the differential potential in the receiving device 130.
And the output was connected to the middle point of the terminating resistor 105. As a result, the intermediate potential of the differential line pair 103A and 103C becomes the intermediate potential Vcm which is the bias voltage output from the bias generation circuit 102, and the differential line pair 103.
The problem of waveform distortions such as A and 103C reflections is solved. If the difference between the power supply voltage VCC1 and the power supply voltage VCC2 and the difference between the ground potential GND1 and the ground potential GND2 between the transmission device 120 and the reception device 130 are not large, respectively, the differential line pair of the transmission device 120 is used. The intermediate potential between 103A and 103C is also approximately Vcm.

The amplitude potential of the differential line pair 103A and 103C is determined by the current flowing through the differential line pair 103A and 103C and the value of the terminating resistor 105. Normally, the impedance of the differential line pair 103A and 103C is 110Ω. Therefore, to achieve impedance matching, the terminating resistor 1
Since the value of 05 is also 110Ω, if the driver circuit 101 of the transmission device 120 causes a current of 2 mA to flow into the transmission line 110, the amplitude voltage of the differential line pair 103A and 103C becomes 220 mV. In addition, the bias potential is 2.0
When V is set, the high-side potential of the differential line pair 103A and 103C is (2.0V + 220mV / 2), which is 2.11.
V, and the low-side potential is (2.0V-220mV /
It becomes 1.89V in 2).

Therefore, if the driver circuit 101 of the transmitting device 120 can stably pass the current of 2 mA to the high-side output terminal (potential is 2.11 V) of the output terminals A and C, the output voltage of 220 mV is small. 40 for amplitude transmission
High-speed data transmission exceeding 0 MHz can be performed without any problem. The power supply potential VCC1 of the driver circuit 101 is
If it is sufficiently higher than the potential of the output terminal on the high side (the potential corresponding to Vd of the driver circuit 101 in FIG. 11 is 2.11V), the PMO of the driver circuit 101 as shown in FIG.
Since a current can flow from the S-transistor 1101 to the output terminal A or C, as described above, 220 m
High-speed data transmission can be performed as a small-amplitude V transmission without any problem.

[0005]

However, between the transmitting device 120 and the receiving device 130, the power supply voltage V
Difference between CC1 and power supply voltage VCC2, and ground potential GN
When the difference between D1 and the ground potential GND2 is large, the potentials of the output terminals A and C of the driver circuit 101 of the transmitting device 120, that is, the potential of the transmission line 110 is not limited to the power supply voltage VCC1 of the driver circuit 101. The power supply voltage VCC1 of the driver circuit 101
Since it may be higher, it may be difficult or impossible to flow a current from the driver circuit 101 to the transmission line 110. That is, in such a state, there arises a problem that data cannot be transmitted.

FIG. 9B shows the ground potential G of the transmitting device 120 in the signal transmitting / receiving circuit 1000 as shown in FIG. 9A.
FIG. 10B is a diagram showing a problem due to the difference between ND1 and the ground potential GND2 of the receiving device 130, and FIG. 10B is a power supply voltage VCC1 of the transmitting device 220 and a power supply voltage of the receiving device 230 in the signal transmitting / receiving circuit 2000 shown in FIG. 10A. It is a figure showing the problem by the difference with VCC2. Hereinafter, a more detailed description will be given with reference to FIGS. 9A to 10B.

9A and 9B show a transmitting device 12
It is assumed that the ground potential GND1 of 0 and the ground potential GND2 of the receiving device 130 are different, specifically, the ground potential GND2 of the receiving device 130 is higher than the ground potential GND1 of the transmitting device 120. in this case,
As shown in FIG. 9B, if the intermediate potential Vcm of the differential line pair 103A and 103C is higher than the power supply voltage VCC1 of the driver circuit 101 of the transmission device 120, the current cannot flow. The difference between these two ground potentials (GND2-
GND1) is likely to occur when transmission and reception are between different devices with different ground points. In particular, when the transmitting device 120 is a stationary video and is supplying power from a power outlet, in this case, the ground potential GND1 is determined by the ground potential of the power outlet. When the other receiving device 130 is a battery-operated video camera and the power is supplied from the built-in battery, its ground is only connected to the housing, so the ground potential of the power outlet is different from the ground potential of itself. It becomes GND2. In particular, as represented by IEEE 1394, etc., when power is supplied from the stationary video to the video camera via a cable, the ground potential GND2 on the video camera side is stationary due to the effect of the resistance of the cable. It is conceivable that the video signal floats about 0.5V to 1.0V from the ground potential GND1 (GND2 = GND1 + 0.5V to 1.0V).

In this case, the intermediate potential Vcm generated in the receiving device 130 has a tendency as shown in FIG. 9B.
In the transmitting device 120, it looks higher than the ground potential GND1 of the transmitting device 120, for example, by 0.5V to 1.0V. For example, the intermediate potential Vcm set with the intention of 2.0V in the receiving device 130 is
Since 0 becomes 2.5 V to 3.0 V, the power supply voltage VCC1 of the driver circuit 101 of the transmitting device 120 is
Is 2.5 V, the potential of Vd shown in FIG. 11 is, for example, 2.61 V to 3.11 V, and VCC1 ≦
Since it becomes Vd, the PMOS transistor 1101 shown in FIG. 11 has a problem that current cannot flow into the output terminals A and C.

Further, FIG. 10A shows a power supply voltage VCC1 of the transmitting device 220 and a power supply voltage VCC of the receiving device 230.
The case where 2 is different is shown. Specifically, it is assumed that the power supply voltage VCC2 of the receiving device 230 is higher than the power supply voltage VCC1 of the transmitting device 220. In this case, as shown in FIG. 10B, the intermediate potential Vcm of the cable becomes higher than the power supply voltage VCC1 of the driver circuit 201 of the transmitting device 220, and therefore the current cannot flow.

The difference between the two power supply voltages (VCC2-VC
C1) is, for example, a transmission / reception device used in a digital video disk device, where the transmission device 220 is an LSI that performs signal processing, and the reception device 230 is an IC that controls a servo motor. Due to the design, it is inevitable. The biggest reason for this is that the LSI that performs signal processing of the transmitting device can be processed by a digital circuit, and thus it can be integrated with a plurality of LSIs that perform more digital processing in one chip.
For the purpose of low cost and reduction of mounting area, it is in the direction of being integrated into one chip by using the most advanced device technology to increase the degree of integration. Therefore, as shown in FIG. 12, the power supply voltage of the CMOS device is 5.0 V → 3.0 V → 2.
There is a trend toward lowering the voltage from 5V to 1.8V.

On the other hand, the IC for controlling the servomotor of the receiving device is an analog circuit and is a semiconductor that drives a mechanical system such as a motor, so that it is composed of a bipolar device and has a power supply voltage of 5 V for each generation. It tends to remain constant. In addition, since there is not much demand for new functions to be added to each generation of this IC, once it is designed, the design of the IC is not normally changed for about five years. Therefore, it is not necessary to change the circuit of the receiving device. Not very realistic. For the above reason, FIGS. 10A and 10B assume that the power supply voltage VCC2 of the receiving device 230 operates at a higher voltage than the power supply voltage VCC1 of the transmitting device 220.

When the receiving device 230 is designed assuming that the potential of 1/2 of the power supply voltage is the intermediate potential Vcm, Vcm =
It becomes 2.5V (= 5V * 1/2). Therefore, when the design rule is 0.25 μm or less in order to increase the degree of integration, the power supply voltage VCC1 of the transmitting device 220 is set to 3.
A person skilled in the art can easily understand from FIG. 10B that a problem that the voltage must be set lower than 3V occurs. Of course, if the design of the receiving circuit is repeated every time when the design of the transmitting circuit is changed, this problem can be solved to some extent, but it is only for redesigning the intermediate potential Vcm, although no new function is added. In addition, determining the product life of the above IC is not realistic because it increases the cost. In addition, when the value of the intermediate potential Vcm must be set to 1.0 V or less due to the decrease in the power supply voltage of the transmitting device, the receiving device is designed to have the intermediate potential Vcm of 1.0 V or less from the power supply of 5 V. It is necessary to make a fundamental circuit change, and it is easy to understand that there are problems in terms of cost increase and stable operation.

Therefore, the present invention operates when the ground potential of the transmitting device of the signal transmitting / receiving device and the ground potential of the receiving device are different, or when the power supply voltage of the receiving device of the signal transmitting / receiving device is higher than the power supply voltage of the transmitting device. Even in such a case, an object thereof is to provide a signal transmitting / receiving device that enables stable data transmission.

[0014]

Signal transmitting and receiving device of the present invention SUMMARY OF THE INVENTION are determined and transmission device for transmitting data, a receiving device for receiving the data, a data line for transmitting the data, a voltage of the data line to a power line for transmitting a bias voltage, wherein a data and signal transmission and reception device connected between the receiving device and the transmitting device by said power supply line, wherein the transmission device, the <br/> data a driver circuit for outputting to the data lines, and generates the <br/> bias voltage, and a bias generating means for outputting to the power line, the receiving device, a terminating resistor connected to the data line , and a receiver circuit for detecting the data from the data lines, the data lines,
It is connected to the power supply line connected to the midpoint of the terminating resistor , and the intermediate potential of the data line is transmitted through the power supply line.
Determined by the bias voltage delivered, which
The above object is achieved.

The bias generating means may include a bias generating circuit and a reference voltage generating circuit.

The data lines may be differential line pairs.

The terminating resistor may be connected so as to short-circuit between the differential line pair, and the power supply line may be connected to substantially the midpoint of the terminating resistor.

The transmitting device may have a first ground potential, the receiving device may have a second ground potential, and the second ground potential may be higher than the first ground potential.

The transmitting device may have a first power supply voltage, the receiving device may have a second power supply voltage, and the second power supply voltage may be higher than the first power supply voltage.

A ground connection line may be further provided for connecting the ground of the transmitting device and the ground of the receiving device.

At least one of the data line and the power line may be flexible.

The ground connection line may be flexible.

The transmission device of the present invention is connected to a data line for transmitting data, in a power supply line for transmitting a bias voltage to determine a voltage of the data line, prior to the receiving device
A transmission device for transmitting serial data, the receiving device, a terminating resistor connected to the data lines, the <br/> data and a receiver circuit for detecting from said data lines, said data lines , Connected to the midpoint of the terminating resistor
Is connected to the power line, the intermediate potential of the data line, pre
Determined by the bias voltage transmitted through the power line
Is a driver circuit for outputting the data to the data lines, the bias voltage generated, and a bias generating means for outputting to the power line, thereby the objective described above being achieved.

The bias generating means may include a bias generating circuit and a reference voltage generating circuit.

It may further be connected to a ground connection line for transmitting the ground potential of the transmitting device to the receiving device.

The receiving device of the present invention is connected to a data line for transmitting data, in a power supply line for transmitting a bias voltage to determine a voltage of the data line from the transmitting device
A receiving device that receives the data, the transmission device, a driver circuit for outputting the data to the data lines, the bias voltage generated, and a bias generating means for outputting to the power line, the with a terminating resistor connected to the data line, and a receiver circuit for detecting the data from the data line, the data line is connected to the connected the power supply line to the midpoint of the final <br/> end resistance And said
The intermediate potential of the data line is transmitted through the power line
Determined by the bias voltage, which achieves the above objectives.

The bias generating means may include a bias generating circuit and a reference voltage generating circuit.

The data line may be a differential line pair, and the terminating resistor may short-circuit the differential line pair, and a bias voltage may be applied to a substantially midpoint of the terminating resistor.

It may be further connected to a ground connection line for transmitting the ground potential of the transmitting device.

The signal transmitting / receiving apparatus of the present invention comprises a transmitting device for transmitting the first data and the second data, and a receiving device for receiving the first data and the second data.
A signal transmitting / receiving apparatus comprising a data line for transmitting first data and second data, wherein the transmitting device and the receiving device are connected by the data line, wherein the transmitting device outputs the first data to the data line. And a circuit for outputting the second data to the data line,
The receiving device includes a terminating resistor connected to the data line, a receiver circuit for detecting data from the data line, and a bias generating means for generating a bias voltage applied to the terminating resistor. The bias voltage is set based on the second data of the above, and thereby the above-mentioned object is achieved.

The bias generating means may include a bias generating circuit and a reference voltage generating circuit.

Among the data lines, the data line transmitting the first data and the data line transmitting the second data may be different.

The data lines may be differential line pairs.

The data line for transmitting the first data may be a differential line pair.

The data line may be a differential line pair, the terminating resistor may be connected so as to short-circuit the differential line pair, and the bias voltage may be applied to substantially the midpoint of the terminating resistor.

The data line transmitting the first data is a differential line pair, the terminating resistor is connected so as to short-circuit the differential line pair, and the bias voltage is substantially at the midpoint of the terminating resistor. It may be applied.

A ground connection line for connecting the ground of the transmitting device and the ground of the receiving device may be further provided.

The data lines may be flexible.

The ground connection line may be flexible.

The transmitting device of the present invention is a transmitting device which is connected to a data line for transmitting the first data and the second data and which transmits the first data and the second data to the receiving device. The device includes a terminating resistor connected to the data line, a receiver circuit that detects the first data from the data line, and a bias that generates a bias voltage to be applied to the terminating resistor based on the second data from the data line. The above-mentioned object is achieved by including a generation circuit and a driver circuit for outputting the first data to the data line and a circuit for outputting the second data to the data line.

The bias generating means may include a bias generating circuit and a reference voltage generating circuit.

Among the data lines, the data line transmitting the first data and the data line transmitting the second data may be different.

It may be further connected to a ground connection line for transmitting the ground potential of the transmitting device to the receiving device.

The data line may be a differential line pair, and the terminating resistor may short-circuit the differential line pair, and a bias voltage may be applied to the substantial midpoint of the terminating resistor.

The receiving device of the present invention is a receiving device which is connected to a data line for transmitting first data and second data and which receives the first data and the second data from the transmitting device. The device includes a driver circuit that outputs the first data to the data line and a circuit that outputs the second data to the data line. The terminal resistor is connected to the data line, and the receiver detects the data from the data line. A receiving device comprising a circuit and bias generating means for generating a bias voltage and outputting it to a terminating resistor, wherein the bias generating means sets the bias voltage based on the second data from the data line, The above object is achieved.

The bias generating means may include a bias generating circuit and a reference voltage generating circuit.

Among the data lines, the data line transmitting the first data and the data line transmitting the second data may be different.

The data line may be a differential line pair, and the terminating resistor may short-circuit the differential line pair, and a bias voltage may be applied to the substantial midpoint of the terminating resistor.

It may be further connected to a ground connection line for transmitting the ground potential of the transmitting device.

The signal transmitting and receiving device of the present invention includes a transmission device for transmitting data, a receiving device that receives the data, is constituted by a differential line pair, and a data line for transmitting the data, the data line a signal transmitting and receiving device connected between the receiving device and the transmitting device by the transmission device comprises a driver circuit for outputting the data to said data <br/> data line, the receiving device, the data with a terminating resistor connected to the line, and a receiver circuit for detecting the data from the data lines, and a bias generator for generating a bias voltage applied to the terminating resistor, wherein the bias generating means, said data lines setting the bias voltage based on the potential, thereby the objective described above being achieved.

The bias generating means may include a bias generating circuit and a reference voltage generating circuit.

[0052]

The terminating resistor may be connected so as to short-circuit between the differential line pair, and the bias voltage may be applied to substantially the midpoint of the terminating resistor.

A ground connection line for connecting the ground of the transmitting device and the ground of the receiving device may be further provided.

The data lines may be flexible.

The ground connection line may be flexible.

The receiving device of the present invention is a receiving device connected to a data line for transmitting data and receiving the data from the transmitting device, wherein the transmitting device is
Comprising a driver circuit for outputting the data to said data line, a terminating resistor connected to the data line, and a receiver circuit for detecting the data from the data line, to generate a bias voltage, and outputs to the terminal resistor A receiving device comprising a bias generating means, wherein the data line is
A flow line pair, the bias generating means sets the bias voltage based on the potential of the data line, thereby the objective described above being achieved.

The bias generating means may include a bias generating circuit and a reference voltage generating circuit.

[0059] The terminating resistor is short-circuited between the differential line pair, the bias voltage to the substantial middle point of the terminating resistor may be applied.

It may be further connected to a ground connection line for transmitting the ground potential of the transmitting device.

The signal transmitting / receiving apparatus of the present invention is configured to transmit a transmitting device for transmitting a plurality of data, a receiving device for receiving a plurality of data, a plurality of data lines for transmitting a plurality of data, and a voltage of the plurality of data lines. A signal transmission / reception apparatus comprising: a power supply line for transmitting a bias voltage to be determined; and a transmission device and a reception device connected by a plurality of data lines and at least one power supply line,
The transmission device includes a plurality of driver circuits that respectively output a plurality of data to a plurality of corresponding data lines, and at least one bias generation unit that generates a bias voltage and outputs the bias voltage to at least one power supply line, The receiving device includes a plurality of terminating resistors that are respectively connected to corresponding data lines of the plurality of data lines and a plurality of receiver circuits that respectively detect a plurality of data from the plurality of data lines. Is connected to at least one corresponding power line through a plurality of corresponding terminating resistors,
Thereby, the above object is achieved.

At least one of the plurality of terminating resistors and at least one power supply line may be connected via an electric resistance.

At least one of the plurality of terminating resistors and at least one power supply line may be connected via an amplifier.

A signal transmitting / receiving apparatus of the present invention receives a transmitting device for transmitting a plurality of first data and at least one second data, and a plurality of first data and at least one second data. Receiving device and a plurality of first
Of a plurality of data lines for transmitting at least one second data and a plurality of data lines, wherein the transmitting device and the receiving device are connected by the plurality of data lines. The receiving device includes a plurality of driver circuits that respectively output one data to a plurality of corresponding data lines and a circuit that outputs at least one and at least one second data to the data lines. A plurality of terminating resistors that are respectively connected to the corresponding data lines of the data lines, a plurality of receiver circuits that detect the plurality of first data from the plurality of data lines, and a bias voltage that is applied to the plurality of terminating resistors. And at least one bias generating means for generating at least one bias generating means for generating at least one bias line from the plurality of data lines. Set the bias voltage based on the second data, thereby the objective described above being achieved.

At least one of the plurality of terminating resistors and at least one bias generating means may be connected via an electric resistance.

At least one of the plurality of terminating resistors and at least one bias generating means may be connected via an amplifier.

The signal transmitting / receiving apparatus of the present invention comprises a transmitting device for transmitting a plurality of data, a receiving device for receiving a plurality of data, and a plurality of data lines for transmitting a plurality of data. A signal transmitting / receiving apparatus in which a transmitting device and a receiving device are connected, wherein the transmitting device includes a plurality of driver circuits that respectively output a plurality of data to a plurality of corresponding data lines, and the receiving device includes a plurality of data. A plurality of terminating resistors connected to the corresponding data lines of the lines, a plurality of receiver circuits for detecting a plurality of data from the plurality of data lines, and at least a bias voltage applied to the plurality of terminating resistors. One bias generating means, wherein the at least one bias generating means is at least one potential in the plurality of data lines. Set the bias voltage on the basis, thereby the objective described above being achieved.

At least one of the plurality of terminating resistors and at least one bias generating means may be connected via an electric resistance.

At least one of the plurality of terminating resistors and at least one bias generating means may be connected via an amplifier.

[0070] signal transmitting and receiving method of the present invention transmits a transmission device for transmitting data, a receiving device for receiving the data, a data line for transmitting the data, a bias voltage for determining the voltage of the data line and a power supply line used, a signal transmitting and receiving method, in the transmitting device, the bias voltage generated, and outputting to the power line, in the terminating resistor in the receiving device
The data line connected to the connected the power supply line to the point
And outputting the data in the receiving device, it includes the steps of detecting the data from the data line, for detecting the data from the data line
In the step, the intermediate potential of the data line is
Determined by the bias voltage transmitted through the source line
Is, thereby, the above-mentioned object can be achieved.

[0071]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the first and second embodiments of the signal transmitting / receiving apparatus of the present invention will be described with reference to FIG.
A description will be given from A to FIG. 2B.

The basic configurations of the first and second embodiments of the signal transmitting / receiving apparatus of the present invention are the following two points 1) and 2). Other than that, the configuration is basically the same as the conventional example.

1) The transmission line is divided into two parts, a data line and a power supply line for transmitting the bias voltage of the data line. When a differential line pair is used as the data line, at least three transmission lines in total extend from the transmitting device to the receiving device. When a single line is used as the data line, at least two transmission lines in total will extend from the transmitting device to the receiving device. In addition, you may add a control line suitably to the transmission line using a differential line pair or a single wire.

2) The bias generation circuit 2 for applying a bias voltage to the receiving end is provided in the transmitting device, and the bias voltage is transmitted by the power supply line running in parallel with the data line.

(Embodiment 1) FIG. 1A and FIG. 1B are the first embodiment of the signal transmitting / receiving apparatus of the present invention, and solve the problem due to the difference in ground potential between the transmitting device and the receiving device of the signal transmitting / receiving apparatus. It is a block diagram of the signal transmitting and receiving apparatus.

The signal transmitting / receiving apparatus 100 of FIG. 1A has a structure in which a transmitting device 18 and a receiving device 19 are connected via a transmission line 17. The transmission line 17 is
The differential line pair 13A and 13C, which are data lines for transmitting data, and the power supply line (bias voltage transmission line) 14B, which transmits a bias voltage that determines the voltage of the differential line pair 13A and 13C. Differential line pair 13A and 13
C and the power supply line 14B, the transmitting device 18, and the receiving device 19 are connected by, for example, connection terminals AF. The transmitting device 18 includes a driver circuit 11 for transmitting data and a bias circuit 12 for generating a bias voltage and transmitting the bias voltage to the receiving device 19, and the receiving device 19 includes a differential line pair. 1
It is provided with a terminating resistor 15 for terminating 3A and 13C, and a receiver circuit 16 for detecting the data transmitted from the transmitting device 18. Differential line pair 13A and 13
C is connected to the power supply line 14B in the receiving device 19 via the terminating resistor 15.

The action / effect produced by the configuration of the embodiment of the present invention will be described below in comparison with the problems of the conventional example.

FIG. 1A shows the ground potential G of the transmitting device 18.
The case where ND1 and the ground potential GND2 of the receiving device 19 are different is shown. Specifically, the ground potential GND2 of the receiving device 19 is equal to the ground potential GND of the transmitting device 18.
It is assumed that the value is higher than 1. Even in this case,
In the signal transmission / reception device 100 of the present invention, the differential line pair 13A and 1A from the power supply voltage VCC1 of the driver circuit 11.
Since the intermediate potential Vcm of 3C is lower, a current can flow.

As can be seen by comparing FIG. 1B and FIG. 9B, in the conventional example, as shown in FIG. 9B, the intermediate potential Vcm generated by the bias generation circuit 102 of the receiving device 130 is equal to the transmission voltage Vcm. In the device 120, for example, 0.5 relative to the ground potential GND1 of the transmitting device 120.
Although it seems to be higher by V to 1.0 V, as in the present embodiment shown in FIG. 1A, the intermediate potential Vcm generated in the bias generation circuit 12 is changed by the power supply line 14B running in parallel with the differential line pair 13A and 13C. When sent to the receiving device 19, the center potential of the differential line pair 13A and 13C is determined through the terminating resistor 15, so the center potential of the differential line pair 13A and 13C on the transmitting device 18 side becomes equal to Vcm. .
The reason for this is that the power supply line 14B that transmits this bias voltage
In the receiving device 19, if the amount of current flowing through the differential line pair 13A and 13C folded back by the terminating resistor 15 is equal, the power supply line 14B connected to the center of the terminating resistor 15 supplies a bias voltage in a DC manner. This is because the current does not flow by itself and the influence of the resistance drop of the transmission line 17 can be ignored.

Of course, considering that a minute current flows due to the imbalance of the resistance and capacitance of the differential transmission line 17 and the imbalance of the differential driver circuit 11, the intermediate potential Vcm should be increased to that extent. By setting, the center potential of the differential line pair 13A and 13C in the transmission device 18 can be easily set to a desired optimum potential within the scope of the embodiment of the present invention.

From the above, in the transmitting device 18,
When the intermediate potential Vcm is set to 2.0V, the center potential of the differential line pair 13A and 13C on the transmission device 18 side is 2.0V, which is almost equal to the intermediate potential Vcm. Power supply voltage VCC1
= 2.5V, the transmitting device 18 can stably supply current to the output terminals A and C.

Therefore, according to the present embodiment, when the transmitting device 18 supplies the power for stationary video from the power outlet, the other receiving device 19 is a battery-operated video camera. In some cases, the power is supplied from the built-in battery, and the ground is only connected to the housing. For example, when the ground potential GND1 of the power outlet of the transmitting device 18 is set to the receiving device 19
Even if it naturally becomes a different ground potential GND2, as is typically represented by IEEE1394,
When power is supplied from the stationary video to the video camera via a cable, the ground potential GND2 on the video camera side is 0.5 V below the ground potential GND1 of the stationary video due to the influence of the resistance of the cable. ~
Floating about 1.0V (GND2 = GND1 + 0.5V ~
Even in the case of 1.0 V), signals can be transmitted and received without any problem.

(Second Embodiment) FIGS. 2A and 2B show a second embodiment of the signal transmitting / receiving apparatus of the present invention, in which the power supply voltage VCC1 of the transmitting device 28 and the power supply voltage VCC2 of the receiving device 29 are different. Then, specifically, it is assumed that the power supply voltage VCC2 of the receiving device 29 is higher than the power supply voltage VCC1 of the transmitting device 28. In this case as well, in the signal transmitting / receiving apparatus 200 of the present invention, the intermediate potential Vcm of the differential line pair 23A and 23C is lower than the power supply voltage VCC1 of the driver circuit 21, so that a current can flow.

It will be apparent from a comparison between FIG. 2B and FIG. 10B. In the conventional example, when the receiver device 230 is designed assuming that the potential of 1/2 of the power supply voltage is the intermediate potential Vcm, for example, Vcm = 2. It was 0.5 V (= 5 V * 1/2). Therefore, if the design rule is 0.25 μm or less in order to increase the degree of integration of the circuit of the transmitting device 220, a person skilled in the art may have a problem that the power supply voltage VCC1 must be set lower than 2.5V. Easy to understand.

On the other hand, in the case of the present embodiment shown in FIG. 2A, as described with reference to FIG. 1A, the center potential of the differential line pair 23A and 23C of the transmitting device 28 is determined only by the transmitting device 28. Therefore, in the case of the present embodiment, a current can be stably supplied from the driver circuit 21 to the receiving device 29, so that data can be transmitted and received without any problem.

Further, in the first and second embodiments of the present invention, as shown in FIG. 2A, a ground connecting line 20 for connecting the ground GND1 of the transmitting device and the ground GND2 of the receiving device is provided. May be. GN like this
When the ground connection line 20 that connects D1 and GND2 is provided, the potential difference between the GND1 of the transmission device 28 and the GND2 of the reception device 29 becomes small, so that the current is more stably supplied from the transmission device 28 to the reception device 29. You can

(Embodiment 3) FIGS. 3A, 3B and 4 show a third embodiment of the signal transmitting / receiving apparatus of the present invention. In the third embodiment, a reference voltage generation circuit 311 that generates a bias voltage is provided in the receiving device 39,
The bias voltage is set by the signal transmitted from the transmitting device 38. The rest of the configuration is basically the same as that of the first and second embodiments of the signal transmission / reception device of the present invention.

In the third embodiment of the present invention, for example, when the signal transmitting / receiving apparatus 300 of the present embodiment is set up (for example, when the power is turned on), a signal for setting the bias voltage is transmitted from the transmitting device 38 to the receiving device. 39 is transmitted to the reference voltage generating circuit 311 of 39, and based on the signal, the reference voltage generating circuit 311 sets an appropriate bias voltage for transmitting data from the transmitting device 38 to the receiving device 39. With the proper bias voltage set in this way, the transmitting device 38 to the receiving device 39
Data can be stably transmitted to the.

The method by which the transmitting device 38 transmits the signal for setting the bias voltage and the method by which the reference voltage generating circuit 311 sets the bias voltage based on the signal can be any method known to those skilled in the art. Done. For example, signals are transmitted and received by the encoder 301 provided in the transmission device 38 and the decoder 302 (FIG. 4) provided in the reference voltage generation circuit 311. As a method of setting the bias voltage by the reference voltage generation circuit 311, for example, the reference voltage generation circuit 311 as shown in FIG. 4 is used.

In the reference voltage generating circuit 311, the power supply VCC3 of the reference voltage generating circuit 311 and the receiving device 39 are used.
Of the plurality of transistors Tr1 and T
r2 to TrN are provided. Gate electrodes of Tr1 to TrN are connected to the decoder 302, respectively.

When the signal transmitted from the transmitting device 38 is input to the decoder 302 in the reference voltage generating circuit 311, the decoder 302 uses Tr1 to T1 based on the signal.
Among rN, a transistor to be turned on and a transistor to be turned off are determined. At this time, Tr1 to TrN
The bias voltage is set to an appropriate value by setting the respective on / off combinations of the above in various patterns. Data can be stably transmitted from the transmitting device 38 to the receiving device 39 by the appropriate bias voltage set in this way.

The transmission of the signal for setting the bias voltage from the transmitting device 38 to the receiving device 39 is
It may be performed using the signal line 34B as shown in FIG. 3A or may be performed using the differential line pair 33A and 33C. When the differential line pairs 33A and 33C are used, the total number of transmission lines 37 connecting the transmitting device 38 and the receiving device 39 can be reduced.

(Embodiment 4) FIGS. 5A and 5B are
The 4th Embodiment of the signal transmission / reception apparatus of this invention is shown. In the signal transmitting / receiving apparatus 500 according to the fourth embodiment of the present invention,
A reference voltage generation circuit 511 that generates a bias voltage is provided in the receiving device 59, the reference voltage generation circuit 511 detects the potentials of the differential line pair 53A and 53C, and sets the bias voltage based on a predetermined program 512. It is configured to do. Since the setting of the bias voltage is performed by the receiving device 59, the power supply line and the signal line are not provided between the transmitting device 58 and the receiving device 59.

The reference voltage generating circuit 511 has a differential line pair 53A.
The method of detecting the potentials of 53C and 53C and the method of setting the bias voltage are performed by any method known to those skilled in the art. The rest of the configuration is basically the same as that of the first and second embodiments of the signal transmission / reception device of the present invention.

In the fourth embodiment of the present invention, preferably, first, differential line pair 53 in reference voltage generating circuit 511 is used.
An arbitrary bias voltage is set to detect the potentials of A and 53C. Then, the potential of the data transmitted from the transmission device 58 is detected, and an appropriate bias voltage is set based on the program 512. With the appropriate bias voltage set in this way, the transmitting device 5
Data can be stably transmitted from 8 to the receiving device 59.

Further, in the third and fourth embodiments of the present invention, as shown in FIGS. 3A and 5A, the transmission device GND1 and the reception device GND are used.
Ground connection lines 30 and 50 may be provided to connect the two. When the ground connection lines 30 and 50 for connecting the GND1 and the GND2 are thus provided, respectively, as shown in FIGS. 3B and 5B, the GND1 of the transmission device is provided.
Since the potential difference between the receiving device and GND2 of the receiving device becomes small, it is possible to more stably flow the current from the transmitting device to the receiving device.

The power supply voltage difference (VCC2-VCC1) between transmission and reception as described above is as follows when the transmission / reception device used in a digital video disk device or the like is taken as an example as described in the section of the problems of the prior art. Since such systematic requirements arise, it can be said that the embodiments of the present invention are inventions capable of solving a very important problem.

FIG. 6 is a schematic block diagram of a digital video disk device 600 to which the present invention is applied. The present invention is used for data transmission between the differential conversion circuit 61 inside the digital section 69 and the writing laser drive circuit 62 of the analog section 68. The rotation of the optical disk 66 is controlled by the mechanism control circuit 165 so that the spindle motor 65 rotates at a predetermined rotation speed. The reading circuit 166 irradiates the track of the optical disc 66 with laser light to read the data recorded on the track. Readout circuit 166
Is output as an analog signal to the read channel circuit 162.
Entered in. The write data to the optical disc 66 is
The differential conversion circuit 61 is transmitted to the writing laser drive circuit 62 via the transmission line 67, and is written on the optical disc 66 using a writing laser (not shown).

As shown in FIG. 6, the transmitting device is an LSI (digital section) 69 for signal processing, and the receiving device is
In the case of an IC (analog unit) 68 that controls a servo motor, an LSI 69 that performs signal processing of a transmission device uses a state-of-the-art CMOS device technology to increase the degree of integration for the purpose of cost reduction and mounting area saving. As shown in FIG. 12, the power supply voltage tends to be reduced to 5.0 V → 3.0 V → 2.5 V → 1.8 V in each generation as shown in FIG.

On the other hand, since the IC 68 for controlling the servo motor of the receiving device is an analog circuit and is a semiconductor that drives a mechanical system such as a motor, it is composed of a bipolar device and the power supply voltage is 5 V, which is the same for each generation. It is constant. In addition, since there is not much demand for adding new functions to each generation of the IC68, once it is designed, the design is not changed for about five years. Therefore, it is very practical to change the circuit of the receiving device. Not at all. Therefore,
A high-speed servo motor control I required for an optical disk drive device, as represented by a digital video disk device, etc.
Power supply voltage V of the receiving device of the transmitter / receiver used in C
The problem that CC2 operates at a voltage higher than the power supply voltage VCC1 of the transmitting device is inevitable. The present invention can provide a low-cost and high-performance signal transmitting / receiving apparatus that can solve such problems.

(Fifth Embodiment) FIGS. 7, 8A and 8
B shows signal transmission / reception devices 700, 800 and 900 according to a fifth embodiment of the present invention. In data transmission between a transmitting device and a receiving device, such as in the digital video disc device 600 illustrated as an example in FIG. 6, a plurality of differential line pairs are provided to transmit a plurality of types of data, and each differential line pair is provided. There may be a case where the bias voltage of the differential line pair must be set. In such a case, if the same number of reference voltage generating circuits are provided to set the bias voltage of each of the plurality of differential line pairs, the configuration of the entire signal transmitting / receiving device becomes large and the cost becomes high. . Therefore, as shown in FIG. 7, a plurality of differential line pairs 740A and 740 are provided by one reference voltage generation circuit 720, one bias generation circuit 722, and one power supply line 750 provided in the transmission device 760.
C, 741A, 741C ... 74NA and 74NC
The bias voltage of each of the terminating resistors 781, 782
... may be set in common via 78N. When there is a difference in the value of the appropriate bias voltage of each differential line pair, for example, the power supply line 750 and each termination resistance 781, 782 ...
Can be adjusted by providing an arbitrary number of electric resistances 731 and amplifiers 732 between and.

Further, as shown in FIG. 8A, a reference voltage generating circuit 820 is installed in the receiving device 870, and the reference voltage generating circuit as described in the third embodiment of the present invention allows the signal from the transmitting device to be transmitted. Even in the case where the bias voltage is set based on, the plurality of differential line pairs 840A, 840C, 841A, using one reference voltage generation circuit 820 and one bias generation circuit 822,
The bias voltages of 841C ... 84NA and 84NC may be commonly set via the terminating resistors 881, 882 ... 88N.

Further, as shown in FIG. 8B, the fourth aspect of the present invention
The reference voltage generation circuit 920 as described in the above embodiment sets the bias voltage based on the program 921, and one reference voltage generation circuit 920 and one bias generation circuit 922 are used to generate a plurality of differential signals. Line pair 9
40A, 940C, 941A, 941C ... 94NA
And the bias voltage of 94NC are applied to the terminating resistor 9
It may be commonly set via 81, 982, ..., 98N.

Also in the embodiment shown in FIGS. 8A and 8B, if there is a difference in the value of the appropriate bias voltage of each differential line pair, the electric resistances 831 and 931 and the amplifier 8 are provided.
Any number of 32 and 932 may be provided.

Further, in the present embodiment, if necessary, GND1 of the transmitting device and GND2 of the receiving device.
You may provide the grounding connection wire which connects with.

The number of reference voltage generating circuits 720, 820 and 920 provided in signal transmitting / receiving devices 700, 800 and 900 shown in FIGS. 7, 8A and 8B is one, but not limited to one. Two or more may be provided to appropriately set the value of the bias voltage. Also, the driver circuits 701 to 70N, 801 to 80N and 901 to 90N in the transmitting devices 760, 860 and 960, and the receiver circuits 711 to 71N and 811 in the receiving devices 770, 870 and 970.
An arbitrary number is set for each of 81N and 911 to 91N depending on the embodiment of the signal transmitting / receiving apparatus.

By thus commonly setting the bias voltages of the plurality of differential line pairs, the overall structure of the signal transmitting / receiving apparatus can be simplified and the cost can be kept low.

Although the cable has been used as the transmission line in the description of the embodiment of the signal transmitting / receiving apparatus of the present invention, a line provided on the substrate may be used instead of the cable. In this case as well, like the cable, the substrate on which the line is provided is preferably flexible.

[0109]

According to the present invention, even when the power supply voltage (VCC2) of the receiving device of the transmitter / receiver operates at a voltage higher than the power supply voltage (VCC1) of the transmitting device, or when the ground potentials of the two are different. Since stable data transmission is possible without changing the design of the IC of the receiving device,
It is possible to provide a high-performance signal transmitter / receiver at low cost.

[Brief description of drawings]

FIG. 1A is a diagram showing a configuration of a signal transmission / reception device according to a first embodiment of the present invention.

FIG. 1B is a diagram showing a ground potential difference between the transmitting device and the receiving device according to the first embodiment of the present invention.

FIG. 2A is a diagram showing a configuration of a signal transmission / reception device according to a second embodiment of the present invention.

FIG. 2B is a diagram showing a power supply voltage difference between the transmission device and the reception device according to the second embodiment of the present invention.

FIG. 3A is a diagram showing a configuration of a signal transmission / reception device according to a third embodiment of the present invention.

FIG. 3B is a diagram showing a power supply voltage difference between the transmitting device and the receiving device according to the third embodiment of the present invention.

FIG. 4 is a diagram showing a configuration of a reference voltage generating circuit according to a third embodiment of the present invention.

FIG. 5A is a diagram showing a configuration of a signal transmission / reception device according to a fourth embodiment of the present invention.

FIG. 5B is a diagram showing a power supply voltage difference between the transmitting device and the receiving device according to the fourth embodiment of the present invention.

FIG. 6 is a schematic configuration diagram of a digital video disc device to which the present invention is applied.

FIG. 7 is a diagram showing a configuration of a signal transmission / reception device according to a fifth embodiment of the present invention.

FIG. 8A is a diagram showing a configuration of a signal transmission / reception device according to a fifth embodiment of the present invention.

FIG. 8B is a diagram showing a configuration of a signal transmission / reception device according to a fifth embodiment of the present invention.

FIG. 9A is a diagram showing a configuration of a conventional signal transmitting / receiving apparatus.

FIG. 9B is a diagram showing a ground potential difference between the transmitting device and the receiving device of the conventional signal transmitting / receiving apparatus.

FIG. 10A is a diagram showing a configuration of a conventional signal transmitting / receiving apparatus.

FIG. 10B is a diagram showing a power supply voltage difference between a transmitting device and a receiving device of a conventional signal transmitting / receiving apparatus.

FIG. 11 is a configuration diagram of a driver circuit of a transmission device of a conventional signal transmission / reception device.

FIG. 12 is a diagram showing the relationship between the degree of integration of CMOS devices and bipolar devices and the power supply voltage.

[Explanation of symbols]

11,21 Driver circuit 12, 22 Bias generator 13A, 13C data line 14, 24 Bias voltage transmission line 15, 25 Termination resistance 16,26 Receiver circuit 17, 27 Transmission line 18, 28 Transmitting device 19,29 Receiving device

Continuation of the front page (56) Reference JP-A-5-46291 (JP, A) JP-A-58-92139 (JP, A) JP-A-10-322403 (JP, A) JP-A-11-146021 (JP , A) JP 5-327565 (JP, A) JP 7-38542 (JP, A) JP 62-180643 (JP, A) JP 62-97453 (JP, A) JP 62-202635 (JP, A) JP 59-77729 (JP, A) JP 60-180259 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04L 25/02 H04L 25/03 H04L 29/00

Claims (56)

(57) [Claims] 1. A transmission device for transmitting data, a reception device for receiving the data, a data line for transmitting the data, and a power supply line for transmitting a bias voltage that determines a voltage of the data line. A signal transmission / reception apparatus in which the transmission device and the reception device are connected by the data line and the power supply line, wherein the transmission device generates a bias voltage and a driver circuit that outputs the data to the data line. And a bias generating means for outputting to the power supply line, wherein the receiving device includes a terminating resistor connected to the data line, and a receiver circuit for detecting the data from the data line, The line is connected to the power supply line connected to the midpoint of the terminating resistor , and the intermediate potential of the data line is
Determined by the bias voltage transmitted through the source line
A signal transmitting / receiving device. 2. The signal transmitting / receiving apparatus according to claim 1, wherein the bias generating means includes a bias generating circuit and a reference voltage generating circuit. 3. The signal transmitting / receiving apparatus according to claim 1, wherein the data line is a differential line pair. 4. The signal transmitting / receiving apparatus according to claim 3, wherein the terminating resistor is connected so as to short-circuit the differential line pair, and the power supply line is connected to a substantially midpoint of the terminating resistor. . 5. The transmitting device has a first ground potential, the receiving device has a second ground potential, and the second ground potential is higher than the first ground potential.
The signal transmitting / receiving apparatus according to claim 1. 6. The transmitting device has a first power supply voltage, the receiving device has a second power supply voltage, and the second power supply voltage is higher than the first power supply voltage.
The signal transmitting / receiving apparatus according to claim 1. 7. The signal transmitting / receiving apparatus according to claim 1, further comprising a ground connection line that connects the ground of the transmitting device and the ground of the receiving device. 8. The signal transmitting / receiving apparatus according to claim 1, wherein at least one of the data line and the power line has flexibility. 9. The signal transmitting / receiving apparatus according to claim 7, wherein the ground connection line is flexible. 10. A transmitting device, which is connected to a data line for transmitting data and a power line for transmitting a bias voltage for determining a voltage of the data line, and which transmits the data to a receiving device, the receiving device Comprises a terminating resistor connected to the data line and a receiver circuit for detecting the data from the data line, wherein the data line is at a midpoint of the terminating resistor .
Connected to the connected power line, the middle of the data line
The electric potential changes to the bias voltage transmitted through the power line.
Therefore, a transmitting device comprising: a driver circuit that is determined according to the above; and a driver circuit that outputs the data to the data line; 11. The transmitting device according to claim 10, wherein the bias generating means includes a bias generating circuit and a reference voltage generating circuit. 12. The transmission device according to claim 10, further connected to a ground connection line for transmitting the ground potential of the transmission device to the reception device. 13. A receiving device connected to a data line for transmitting data and a power supply line for transmitting a bias voltage for determining a voltage of the data line, the receiving device receiving the data from a transmitting device, the transmitting device Includes a driver circuit that outputs the data to the data line and a bias generation unit that generates the bias voltage and outputs the bias voltage to the power supply line, and a terminating resistor connected to the data line, and the data A receiver circuit for detecting from a data line, wherein the data line is connected to the power supply line connected to the midpoint of the terminating resistor , and the intermediate potential of the data line is the electric potential.
Determined by the bias voltage transmitted through the source line
That, the receiving device. 14. The receiving device according to claim 13, wherein the bias generating means includes a bias generating circuit and a reference voltage generating circuit. 15. The data line is a differential line pair, the terminating resistor short-circuits the differential line pair, and the bias voltage is applied to a substantially midpoint of the terminating resistor. The receiving device according to claim 13. 16. The receiving device according to claim 13, further connected to a ground connection line for transmitting the ground potential of the transmitting device. 17. A transmitting device for transmitting first data and second data, a receiving device for receiving the first data and the second data, the first data and the second data And a driver circuit for outputting the first data to the data line, the signal line transmitting and receiving device comprising: A circuit that outputs the second data to the data line, the receiving device includes a terminating resistor connected to the data line, a receiver circuit that detects the data from the data line, and the terminating resistor. Bias generating means for generating a bias voltage applied to the second data line from the data line.
A signal transmitting / receiving device, wherein the bias voltage is set based on the data of 1. 18. The signal transmitting / receiving apparatus according to claim 17, wherein the bias generating means includes a bias generating circuit and a reference voltage generating circuit. 19. The signal transmitting / receiving apparatus according to claim 17, wherein, of the data lines, a data line transmitting the first data and a data line transmitting the second data are different. 20. The signal transmitting / receiving apparatus according to claim 17, wherein the data line is a differential line pair. 21. The signal transmitting / receiving apparatus according to claim 19, wherein the data line for transmitting the first data is a differential line pair. 22. The signal transmission / reception according to claim 20, wherein the termination resistor is connected so as to short-circuit the differential line pair, and the bias voltage is applied to a substantially midpoint of the termination resistor. apparatus. 23. The signal transmission / reception according to claim 21, wherein the termination resistor is connected so as to short-circuit the differential line pair, and the bias voltage is applied to a substantially midpoint of the termination resistor. apparatus. 24. The signal transmitting / receiving apparatus according to claim 17, further comprising a ground connection line that connects the ground of the transmitting device and the ground of the receiving device. 25. The signal transmitting / receiving apparatus according to claim 17, wherein the data line has flexibility. 26. The signal transmitting / receiving apparatus according to claim 24, wherein the ground connection line is flexible. 27. A transmitting device connected to a data line for transmitting first data and second data, for transmitting the first data and the second data to a receiving device, wherein the receiving device is A terminating resistor connected to the data line, a receiver circuit for detecting the first data from the data line, and a bias voltage applied to the terminating resistor based on the second data from the data line. A transmitting device, comprising: a bias generating unit that generates the first data; and a driver circuit that outputs the first data to the data line, and a circuit that outputs the second data to the data line. 28. The transmitting device according to claim 27, wherein the bias generating means includes a bias generating circuit and a reference voltage generating circuit. 29. The transmitting device according to claim 27, wherein among the data lines, a data line transmitting the first data and a data line transmitting the second data are different. 30. The transmitting device according to claim 27, further connected to a ground connection line for transmitting the ground potential of the transmitting device to the receiving device. 31. The data line is a differential line pair, the terminating resistor short-circuits the differential line pair, and the bias voltage is applied to a substantially midpoint of the terminating resistor. The transmitting device according to claim 27. 32. A data line for transmitting first data and second data, the first line from a transmitting device being connected to the first line.
Receiving the second data and the second data, the transmitting device outputs a driver circuit that outputs the first data to the data line, and outputs the second data to the data line. A receiving device comprising: a circuit, a terminating resistor connected to the data line, a receiver circuit for detecting the data from the data line, and a bias generating means for generating a bias voltage and outputting the bias voltage to the terminating resistor. The bias generating means is configured to output the second signal from the data line.
A receiving device for setting the bias voltage based on the data of 1. 33. The receiving device according to claim 32, wherein the bias generating means includes a bias generating circuit and a reference voltage generating circuit. 34. The receiving device according to claim 32, wherein, of the data lines, a data line transmitting the first data and a data line transmitting the second data are different. 35. The data line is a differential line pair, the terminating resistor short-circuits the differential line pair, and the bias voltage is applied to a substantially midpoint of the terminating resistor. The receiving device according to claim 32. 36. The receiving device according to claim 32, further connected to a ground connection line for transmitting the ground potential of the transmitting device. 37. A transmitting device for transmitting data, a receiving device for receiving the data, and a data line for transmitting the data, the data line being constituted by a differential line pair, and transmitting the data. A signal transmitting / receiving apparatus connected to the receiving device, wherein the transmitting device includes a driver circuit that outputs the data to the data line, the receiving device includes a terminating resistor connected to the data line, A receiver circuit that detects data from the data line; and a bias generation unit that generates a bias voltage to be applied to the terminating resistor, wherein the bias generation unit sets the bias voltage based on the potential of the data line. Signal transmitter and receiver. 38. The signal transmitting / receiving apparatus according to claim 37, wherein the bias generating means includes a bias generating circuit and a reference voltage generating circuit. 39. The signal transmission / reception according to claim 37 , wherein the termination resistor is connected so as to short-circuit the differential line pair, and the bias voltage is applied to a substantially midpoint of the termination resistor. apparatus. 40. The signal transmitting / receiving apparatus according to claim 37, further comprising a ground connection line that connects the ground of the transmitting device and the ground of the receiving device. 41. The signal transmitting / receiving apparatus according to claim 37, wherein the data line has flexibility. 42. The ground connection line is flexible, 請
The signal transmission / reception device according to claim 40 . 43. A receiving device connected to a data line for transmitting data and receiving the data from a transmitting device, wherein the transmitting device comprises a driver circuit for outputting the data to the data line, A receiving device comprising a terminating resistor connected to a line, a receiver circuit for detecting the data from the data line, and a bias generating unit for generating a bias voltage and outputting the bias voltage to the terminating resistor, wherein the data line is A receiving device which is a differential line pair, wherein the bias generating means sets the bias voltage based on the potential of the data line. 44. The receiving device according to claim 43 , wherein the bias generating means includes a bias generating circuit and a reference voltage generating circuit. 45. The terminating resistor, the short across the differential line pair, the bias voltage to the substantial middle point of the terminating resistor is applied, the receiving device according to claim 43. 46. The receiving device according to claim 43 , further connected to a ground connection line for transmitting the ground potential of the transmitting device. 47. A transmitting device for transmitting a plurality of data, a receiving device for receiving the plurality of data, a plurality of data lines for transmitting the plurality of data, and a bias for determining a voltage of the plurality of data lines. At least one power supply line for transmitting a voltage, comprising: a signal transmitting and receiving device, wherein the transmitting device and the receiving device are connected by the plurality of data lines and the at least one power supply line, wherein the transmitting device is A plurality of driver circuits that respectively output the plurality of data to the corresponding plurality of data lines; and at least one bias generation unit that generates the bias voltage and outputs the bias voltage to the at least one power supply line. , The receiving device includes a plurality of terminals, each of which is connected to a corresponding one of the plurality of data lines. A resistor and a plurality of receiver circuits that respectively detect the plurality of data from the plurality of data lines, wherein the plurality of data lines correspond to the at least one corresponding one of the plurality of terminating resistors. A signal transmitting / receiving device connected to a power line. 48. The signal transmitting / receiving apparatus according to claim 47 , wherein at least one of the plurality of terminating resistors and the at least one power supply line are connected to each other via an electric resistance. 49. The signal transmitting / receiving apparatus according to claim 47 , wherein at least one of the plurality of terminating resistors and the at least one power supply line are connected via an amplifier. 50. A transmitting device for transmitting a plurality of first data and at least one second data, and a receiving device for receiving the plurality of first data and the at least one second data. A plurality of data lines for transmitting the plurality of first data and the at least one second data, and a signal transmitting / receiving apparatus in which the transmitting device and the receiving device are connected by the plurality of data lines. Wherein the transmitting device outputs a plurality of the first data to the corresponding plurality of data lines, and a plurality of driver circuits, and at least one of the at least one second data. A circuit for outputting to a data line, wherein the receiving device comprises a plurality of terminating resistors respectively connected to corresponding data lines of the plurality of data lines. A plurality of receiver circuits that respectively detect the plurality of first data from the plurality of data lines, and at least one bias generation unit that generates a bias voltage to be applied to the plurality of termination resistors. A signal transmitting / receiving device, wherein one bias generating means sets the bias voltage based on the at least one second data from the plurality of data lines. 51. The signal transmitting / receiving apparatus according to claim 50 , wherein at least one of the plurality of terminating resistors and the at least one bias generating means are connected to each other via an electric resistance. 52. The signal transmitting / receiving apparatus according to claim 50 , wherein at least one of the plurality of terminating resistors and the at least one bias generating means are connected via an amplifier. 53. A transmission device for transmitting a plurality of data, a reception device for receiving the plurality of data, and a plurality of data lines for transmitting the plurality of data, wherein the transmission is performed by the plurality of data lines. A signal transmitting / receiving apparatus in which a device and the receiving device are connected, wherein the transmitting device includes a plurality of driver circuits that respectively output the plurality of data to the corresponding plurality of data lines, and the receiving device is A plurality of terminating resistors that are respectively connected to corresponding data lines of the plurality of data lines, a plurality of receiver circuits that respectively detect the plurality of data from the plurality of data lines, and a plurality of terminating resistors. At least one bias generating means for generating a bias voltage to be applied, said at least one bias generating means At least one of the signal transmitting and receiving device for setting the bias voltage based on the potential of the plurality of data lines. 54. The signal transmitting / receiving apparatus according to claim 53 , wherein at least one of the plurality of terminating resistors and the at least one bias generating means are connected via an electrical resistor. 55. The signal transmitting / receiving apparatus according to claim 53 , wherein at least one of the plurality of terminating resistors and the at least one bias generating means are connected via an amplifier. 56. A transmitting device for transmitting data, a receiving device for receiving the data, a data line for transmitting the data, and a power supply line for transmitting a bias voltage for determining a voltage of the data line. A method for transmitting and receiving a signal, comprising: generating the bias voltage in the transmitting device and outputting the bias voltage to the power source line; and the power source line connected to a midpoint of a terminating resistor in the receiving device A step of outputting the data to the data line connected to the data line; and a step of detecting the data from the data line in the receiving device, the step of detecting the data from the data line.
The intermediate potential of the data line is transmitted through the power line.
A method of transmitting and receiving a signal , which is determined by the bias voltage transmitted.