JPS5946148B2 - insulation device - Google Patents

Description

[Detailed description of the invention] The present invention relates to an insulating device.

Isolation devices are used to isolate and couple two electrical devices.

Since power and signals are supplied between two electrical devices, either from one to the other or to each other, an isolation device is required for each.

Because power and signals have different electrical forms and energy levels, it is common to use dedicated isolation devices for power and signals, and some types of signals also have different electrical types. Due to the different shapes, a dedicated insulating device suitable for each N is normally used. For this reason, a plurality of insulating devices are interposed at the joint between the two electrical devices, which inevitably complicates the configuration and increases the number of parts. An object of the present invention is to provide an isolation device that is capable of insulating power and a plurality of signals with a single insulator, and also capable of bidirectionally transmitting signals between two electrical devices via an insulator. It's about doing.

In the present invention, one electric device and the other electric device are connected to the primary side and the secondary side of one transformer, and the one electric device includes a high-frequency oscillator that generates a clock signal,
A modulation circuit that receives a data signal and binary-modulates the clock signal according to the data signal, and a switching device that changes the voltage across the primary coil of the transformer based on the binary modulation signal from the modulation circuit. a load detector that detects a signal transmitted from the other electrical device based on a change in voltage across a resistor connected to the center tap of the primary coil; The electrical device includes a rectifier circuit that rectifies the high frequency AC power transmitted from the one electrical device to obtain power supply power, and demodulates the high frequency AC power transmitted from the one electrical device into a data signal and a clock signal. a demodulation circuit; a signal processing circuit that is driven by the power supply from the rectifier circuit and performs signal processing on the data signal and clock signal from the demodulation circuit and outputs return data; The insulation device is characterized in that it has a modulation circuit that modulates and outputs a signal to be transmitted to the load detector.

Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a conceptual block diagram of an embodiment of the present invention. In FIG. 1, 1 is a high frequency oscillator, 2 is a modem/modulator 3 is a switching circuit, and 4 is a transformer. The modulation circuit MOD of the modulation/demodulation section 2 binary-modulates the clock signal output from the high frequency oscillator 1 according to the digital input data SD and supplies it to the switching circuit 3. The switching circuit 3 alternately connects both ends of the primary coil of the transformer 4 to the common point in accordance with the applied signal. Since a DC power supply voltage is applied to the center tap of the primary coil of the transformer 4, a high frequency AC voltage is induced by alternately connecting both ends of the primary coil to a common. A resistor is provided in the power supply path of the center tap of the transformer 4, and the voltage drop thereof is applied to the demodulation circuit DEM of the modulation/demodulation section 2 through an amplifier. On the secondary side of the transformer 4, 5 is a modulation/demodulation section, 6 is a rectifier circuit, and 7 is a signal processing circuit.

The data signal SD and clock CLK are demodulated from the induced voltage of the secondary coil of the transformer 4 by the demodulation circuit DEM of the modulation/demodulation section 5, and these are given to the signal processing circuit 7. The induced voltage in the secondary coil of the transformer 4 is converted into a DC voltage by a rectifier circuit 6, and is applied to a signal processing circuit 7 as a power supply voltage. The signal processing circuit 7 is energized by this power supply and processes the data signal SD according to a predetermined function. The clock signal is synchronized with the output of the high frequency oscillator 1 and is used as a basic timing signal for data processing operations. The signal processing circuit 7 generates return data RD as a result of data processing. This data RD is applied to the secondary side of the transformer 4 through the modulation circuit MOD of the modulation/demodulation section 5, and its load amount is binary-modulated. By binary modulating the load amount of the transformer 4, the current given to the center tap from the DC power supply on the primary side changes in a binary manner, and the voltage drop on the resistor 6 changes in a binary manner, so the load amount changes in a binary manner. changes in can be detected. This detection signal is input to the demodulation circuit DEM through an amplifier, and the return data RD is restored by the demodulation circuit DEM. The modulation circuit MOD of the modulation/demodulation section 2 includes amplitude modulation, FSK/
Modulation circuits of various types, such as PSK modulation, can be used, and the demodulation circuit DEM of the modulation/demodulation section 5 can also be of various types corresponding thereto.

Modulation circuit MOD of modem section 5 and demodulation circuit D of modem section 2
The same applies to EM. Several examples of modulation and demodulation circuits are shown in FIGS. 2-5. FIG. 2 shows an example of amplitude modulation/demodulation, in which a pair of AND switches (NAND gates) 31 and 32 whose operation is enabled/disabled is controlled by the logical value of input data SD, are operated in opposite phases. It is driven by a clock (output of a high-frequency oscillator) CLK and turned on and off alternately, and both ends of the primary coil of the transformer 4 are alternately connected to the common point, thereby rectifying the alternating current voltage induced in the secondary coil. This is to obtain demodulated data D.

The AC voltage induced in the secondary coil of the transformer 4 has the same frequency as the clock signal and the amplitude is modulated on and off according to the logical value of the input data SD. Can be restored. The rectified voltage is charged into a capacitor and used as a power supply voltage. A clock signal CLK is generated from the AC voltage before rectification.
is extracted. A transistor 5 is connected between the output terminals of the rectifier circuit.
0 collector-emitter circuits are connected in parallel, and the load amount of the 9-transformer 4 is modulated in a binary manner by turning on and off the transistor 50 according to the logic value of the return data RD from the signal processing circuit. This modulation of the load amount is demodulated by the demodulation circuit DEM on the primary side to restore the return data RD. FIG. 3 shows an example of a phase modulation circuit, which consists of a combination of a D-type flip-flop circuit 21 and logic elements 22 to 26. The D-type flip-flop circuit is controlled by input data SD and a clock signal CLK. By controlling logic elements 24 and 25 using the output of the D-type flip-flop circuit 21 and the clock signal CLK, an output signal obtained by phase modulating the clock signal CLK with the input data SDVC is obtained.

FIG. 4 shows an example of a differential phase modulation circuit, which is composed of a combination of a JK flip-flop circuit 21' and logic elements 22' to 25', and the JK flip-flop circuit 21' is controlled by input data SD and a clock signal CLK. By controlling the logic elements 24' and 25' using the output of the JK flip-flop circuit 2V and the clock signal CLK, an output signal obtained by differentially phase modulating the clock signal CLK with the input data is generated. I'm starting to get it.

FIG. 5 shows a demodulation circuit for FSK/PSK modulated signals, which includes two monostable multivibrators 5.
The modulated signal is input to monostable multivibrators 51, 52, and the output signals of these monostable multivibrators 51, 52 are used as a D-type flip-flop circuit. It controls the flip-flop circuit 53 and also controls its own input gate with the output of the monostable multivibrator 52 to obtain demodulated data from the D-type flip-flop circuit 53 and demodulated clock from the monostable multivibrator 52. It's becoming like that.

In the device of FIG. 1 constructed as described above, power, data, and clock are transmitted from the primary side to the secondary side through a single insulator, or transformer 4, and from the secondary side to the primary side. A signal is transmitted to the side in the form of load modulation.

That is, power and multiple signals can be isolated by a common isolator. A more detailed embodiment of the invention is shown in FIG.

The device shown in FIG. 6 is an example in which an analog/pulse width conversion circuit is used as the signal processing circuit 7 on the secondary side in the isolation method using the amplitude modulation/demodulation method shown in FIG. The analog/pulse width conversion circuit 7 is a known pulse width conversion device consisting of a closed loop connection of an integrating circuit 71 and a flip-flop circuit 72, and converts an analog input voltage Ei into a pulse width signal. In this case, the data SD from the primary side is used as a synchronizing signal for pulse width conversion, and is applied to the flip-flop circuit 72 to define the period of pulse width conversion. The return data RD converted into pulse width drives the transistor 50 by 1, and the load modulation of the transformer 4 is performed by this transistor 50. A plurality of secondary side devices can be connected in parallel to a common primary side device.

An example of this is shown in FIG. Figure 7 (IC. dies, the primary device specifies a specific secondary device using data SD and gives a command, and in response, the designated secondary device returns data RD. All The power source for the secondary side device is obtained by rectifying the high frequency alternating current sent from the primary side device. According to such an insulating device, the following effects can be obtained.

That is, high frequency AC power is transmitted from one electrical device to the other electrical device via one transformer 4, and in the other electrical device, power is obtained from the rectifier circuit 6, and power is supplied to the demodulating circuit DEM. Take out the data signal and clock signal.

From this, power and multiple signals can be isolated with one insulator. Furthermore, since both electrical devices are provided with modulation/demodulation sections, signals can be transmitted bidirectionally between the two electrical devices via the insulator.

[Brief explanation of drawings]

FIG. 1 is a conceptual configuration diagram of an embodiment of the present invention, FIGS. 2 to 5 are circuit diagrams of a specific example of a part of the device shown in FIG. 1, and FIG. 6 is an electrical configuration of a specific example of the present invention. 7 are conceptual configuration diagrams of an application example of the present invention. DESCRIPTION OF SYMBOLS 1...High frequency oscillator, 2...Modulation/demodulation section, 3...Switching circuit, 4...Transformer, 5...Modulation/demodulation section, 6 ... Rectifier circuit, 7... Signal processing circuit.

Claims (1)

[Claims] 1 One electric device and the other electric device are connected to the primary and secondary sides of one transformer, and the one electric device has a high frequency oscillator that generates a clock signal and a high frequency oscillator that receives a data signal. a modulation circuit that binary-modulates the clock signal according to the data signal; a switching circuit that changes the voltage across the primary coil of the transformer based on the binary modulation signal from the modulation circuit; and a load detector that detects a signal transmitted from the other electrical device to the one device via the transformer based on a change in voltage across a resistor connected to the center tap of the next coil. , the other electric device includes a rectifier circuit that rectifies the high frequency AC power transmitted from the one electric device to obtain power supply power, and a rectifier circuit that rectifies the high frequency AC power transmitted from the one electric device, and converts the high frequency AC power transmitted from the one electric device into a data signal and a clock. a demodulation circuit that demodulates the signal; a signal processing circuit that is driven by power from the rectifier circuit and performs signal processing on the data signal and clock signal from the demodulation circuit and outputs return data;
An insulating device comprising: a modulation circuit that modulates return data from the signal processing circuit again and outputs a signal to be transmitted to one electrical device.