CN219204076U

CN219204076U - High-side driving output circuit

Info

Publication number: CN219204076U
Application number: CN202222956054.8U
Authority: CN
Inventors: 田跃龙; 马江涛; 刘汝涛; 陈志名
Original assignee: Wuhan Zhixing Technology Co ltd
Current assignee: Wuhan Zhixing Technology Co ltd
Priority date: 2022-11-07
Filing date: 2022-11-07
Publication date: 2023-06-16
Anticipated expiration: 2032-11-07

Abstract

The utility model discloses a high-side drive output circuit, which comprises: a signal input terminal for receiving an input signal; the output module comprises a first switching device connected with a power supply and a second switching device connected with a grounding end, and the first switching device and the second switching device are connected through the output end; the switch control module is connected between the signal input end and the output module; the output module further comprises a short-circuit protection module connected with the first switching device, and the short-circuit protection module turns off the first switching device when the current flowing through the first switching device exceeds a preset value; the first switching device and the second switching device are controlled to be switched on and off by the switching control module according to the high level or low level state of the input signal, so that: when the input signal is in a high level, the output module outputs a voltage signal which is the same as that of the power supply, when the input signal is converted from the high level to the low level or the high resistance state, the output module does not output the signal, and the high side drives the output circuit to discharge through the conducted second switching device.

Description

High-side driving output circuit

Technical Field

The utility model relates to the field of circuits, in particular to a high-side output driving circuit technology.

Background

In the known circuit design field, when a power supply supplies power to an electronic device, power-on time sequence of some circuit modules needs to be controlled in an internal circuit of the device, or on-off of the power supply of some circuit modules needs to be controlled, or on/off of the power supply needs to be controlled when the power supply is provided for an external device.

The intelligent driving bottom driving controller product can be connected with a plurality of peripheral devices, such as an IMU (Inertial Measurement Unit ) module, an acousto-optic warning device, a laser radar, a wheel speed meter module, a temperature acquisition module and the like. When the circuit module and the peripheral equipment are powered, the power on and off of the circuit is controlled, the driving circuit is required to be cut off immediately under the condition of short circuit, and the circuit is protected from dangers such as heating, breakdown damage, fire and the like. Meanwhile, the residual voltage on the power supply line of the load module can be quickly released after the load is powered by the switching power supply, and reliable power supply stability is provided for the next quick start. In addition, the requirements of the circuit start-up momentary load on the power supply are also considered.

In the circuit design of the prior art, the currently used short-circuit protection circuit is generally a current detection IC, most of the short-circuit protection circuits do not have a rapid discharging function, and the short-circuit protection circuit has a complex structure and is high in price.

In addition, the short-circuit protection circuit in the prior art only plays roles of short-circuit protection and switch control, but cannot reduce the requirement of a circuit module or peripheral equipment on power supply at the starting moment, and cannot provide a function of rapidly discharging a power line.

Therefore, it would be beneficial to design a circuit that can achieve high side drive output supporting rapid discharge, and reduce the power supply capability requirements at start-up instants, and that has the capability of rapid discharge after power failure.

Disclosure of Invention

In order to solve at least one of the problems in the prior art, the present utility model provides a high-side driving output circuit, comprising:

a signal input terminal for receiving an input signal, the input signal being either a high level or a low level,

the output module comprises a first switching device connected with a power supply and a second switching device connected with a grounding end, the first switching device and the second switching device are connected through the output end,

the switch control module is connected between the signal input end and the output module,

wherein the output module further comprises a short-circuit protection module connected with the first switching device, the first switching device is turned off when the current flowing through the first switching device exceeds a preset value,

the first switching device and the second switching device are controlled to be switched on and off by the switching control module according to the high level or low level state of the input signal, so that:

when the input signal is in a high level, the output module outputs a voltage signal which is the same as that of the power supply, when the input signal is converted from the high level to the low level, the output module does not output the signal, and the high side drives the output circuit to discharge through the conducted second switching device.

The circuit provided by the utility model can solve the problem of instantaneous output current overshoot when the internal module and the external equipment of the controller circuit are electrified, and can rapidly discharge the residual voltage on the circuit, so that the stable and reliable output power supply voltage during rapid electrification can be ensured no matter the circuit is powered off due to a fault or the situation that the power supply needs to be switched, and the stable power supply to the subsequent power supply can be ensured.

In some embodiments of the present utility model, the short circuit protection module may include a protection device, a current limiting resistor, and a current sampling resistor, the protection device being selected from a triode.

In some embodiments of the present utility model, the switch control module may include a third switching device and a first voltage dividing circuit.

In some embodiments of the present utility model, the first voltage dividing circuit includes a series resistor having one end connected to the signal input terminal and the other end grounded, wherein the connection terminals of two resistors in the series resistor are connected to the control terminal of the third switching device.

In some embodiments of the present utility model, the third switching device may turn on the first switching device through the second voltage dividing circuit.

In some embodiments of the utility model, the third switching device may be a transistor.

In some embodiments of the present utility model, the second voltage dividing circuit may include a series resistor having one end connected to the power supply and the other end grounded through the third switching device, wherein the connection ends of two resistors in the series resistor are connected to the control end of the first switching device.

In some embodiments of the utility model, the protection device may use a triode.

In some embodiments of the utility model, the first switching device, the second switching device and the third switching device are selected from a MOS field effect transistor or a triode, wherein the first switching device and the second switching device may be complementary.

In some embodiments of the present utility model, the third switching device may employ an NPN transistor. In this case, the emitter of the third switching device is grounded, and the collector is connected to the second voltage dividing circuit.

In some embodiments of the present utility model, the protection device may be a PNP transistor, and the first switching device may be a PMOS field effect transistor. In this case, the collector of the protection device is connected to the gate of the first switching device, the emitter of the protection device is connected to the power supply, the base of the protection device is connected to one end of the current limiting resistor, and the other end of the current limiting resistor is connected to the source of the first switching device and to the power supply by means of a current application resistor. In addition, the second switching device may employ an NMOS field effect transistor. At this time, the gate of the second switching device is connected to the collector of the third switching device and one end of the voltage dividing resistor, while the other end of the voltage dividing resistor is grounded, and the drain of the second switching device is connected to the output terminal through another resistor.

In some embodiments of the present utility model, the circuit may further include a soft start control module, one end of which is connected to the control terminal of the first switching device, and the other end of which is connected to the circuit output terminal.

When the third switching device is turned on, the embodiment can play a role in increasing the on time of the first switching device and reducing the instantaneous impact of the load on the power supply.

In some embodiments of the present utility model, the soft start control module may be a capacitor.

In some embodiments of the present utility model, the output module of the circuit may further include a diode having an anode connected to the first switching device and a cathode connected to the second switching device. The embodiment can prevent the power supply from being damaged when the signal output end is short-circuited with the outside.

According to the high-side driving output circuit, through a specific circuit structural design, when external equipment and a module are powered so as to control the power on and off of peripheral equipment, the circuit is subjected to overcurrent protection design, so that the circuit can be immediately cut off under the overcurrent condition, and meanwhile, the residual voltage on the power supply line of the external load module is quickly discharged after the power supply is switched, and the power stability of the circuit module with the requirement on power on in the quick switching process is effectively ensured. Therefore, the high-side output has the function of ensuring that the load module can be normally started and shut down, and equipment connected with the high-side drive output circuit can not be influenced by switching on and off of a power supply, so that the high-side drive output circuit has wide applicability.

Drawings

Fig. 1 is a schematic diagram of a high-side driving output circuit according to an embodiment of the present utility model.

Fig. 2 is a schematic structural diagram of a switch control module according to an embodiment of the present utility model.

Fig. 3 is a schematic circuit diagram of a high-side driving output circuit according to an embodiment of the present utility model.

Detailed Description

In order to make the objects, technical solutions and advantages of the present utility model more apparent, the present utility model will be described in further detail with reference to the accompanying drawings and specific embodiments. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present utility model may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the utility model to those skilled in the art.

Referring to fig. 1, a schematic diagram of a high-side driving output circuit according to an embodiment of the present utility model is shown. As shown in fig. 1, the high-side driving output circuit provided by the utility model mainly comprises a signal input end 10, a switch control module 20, an output module 30 and a signal output end 40.

The signal input terminal 10 is configured to receive an input signal, where the state of the input signal may be a high level or a low level, or may be a high resistance state.

The output module 30 includes a first switching device 31 and a second switching device 32 for outputting a signal of a corresponding state according to a state of an input signal. Wherein the first switching device 31 is connected to a power supply 33 and the second switching device 32 is connected to a ground terminal 34. The first switching device 31 and the second switching device 32 are connected to the signal output terminal 40, and can output signals in a high-side driving manner.

One end of the switch control module 20 is connected to the signal input terminal 10, and the other end is connected to the control terminal of the first switching device 31 and the control terminal of the second switching device 32. The switch control module 20 is used for controlling the outputs of the first switching device 31 and the second switching device 32. Specifically, it is used to control the on/off of the first switching device 31 and the second switching device 32 according to the state (high level, or low level and high resistance state) of the input signal:

when the input signal is at a high level, the switch control module 20 controls the first switching device 31 to be turned on and the second switching device 32 to be turned off, so that the signal output end 40 connected with the output module 30 outputs a voltage signal identical to the power supply, namely, the peripheral load connected with the subsequent stage is electrified;

when the input signal is in a low level or high resistance state, the switch control module 20 controls the first switching device 31 to be turned off and the second switching device 32 to be turned on, so that the output module 30 does not output a signal, i.e. the peripheral load connected to the subsequent stage is powered down. At the same time, the output module 30 discharges through the turned-on second switching device 32, and releases the residual charge in the high-side driving output circuit after power failure.

The output module 30 further includes a short-circuit protection module 35 connected to the first switching device 31, where the short-circuit protection module 35 turns off the first switching device 31 when the current flowing through the first switching device 31 exceeds a preset value, so as to implement an overcurrent protection function of the external interface.

The circuit structure can realize high-side driving output with the overcurrent protection function in the power supply power-on process and after power-on and the rapid discharging function when the power supply is powered down, and particularly when the external power supply fails to cause sudden power failure, the circuit can ensure the stable state of power supply power-on again.

In one embodiment, the switch control module 20 may be implemented using a switching device and a voltage divider circuit.

For example, referring to fig. 2, a schematic diagram of a switch control module 20 according to an embodiment of the present utility model is shown. The switch control module 20 includes a voltage dividing circuit 21 (referred to as a first voltage dividing circuit) and a third switching device 22. The voltage divider circuit 21 may include series resistors R1 and R2 having one end connected to the signal input terminal 10 and the other end grounded. Wherein, one end of the first resistor R1 is connected with the signal input end 10, and the other end is connected with the control end of the third switching device 22; one end of the second resistor R2 is connected to the control terminal of the third switching device 22, and the other end is grounded. The first resistor R1 is connected to the control terminal of the third switching device 22 and to one end of the second resistor R2 connected to the control terminal of the third switching device 22. That is, the connection terminal of the first resistor R1 and the second resistor R2 is connected to the control terminal of the third switching device 22.

Based on the above configuration, the voltage dividing circuit 21 can control the turn-off of the third switching device by the voltage division of the first resistor R1 among the series resistors in the series resistors R1, R2 when the input signal is in the low level or high resistance state. On the basis, when the input signal is in a low level or high resistance state, the voltage dividing circuit outputs a corresponding level to the third switching device, so that the third switching device works (for example, is turned off), and the first switching device in the output module is turned off and the second switching device is turned on, so that the whole circuit is ensured not to output the signal, namely, power is not supplied to a subsequent module or equipment, and meanwhile, the residual voltage in the circuit is released through the grounded second switching device.

It should be understood by those skilled in the art that the switch control module may take other forms as long as the operating state of the third switching device can be controlled so that when the input is at a high level, the third switching device controls the first switching device to be turned on and the second switching device to be turned off to realize the output of the high level signal, and when the input signal is at a low level or high impedance, the third switching device controls the first switching device to be turned off so that the circuit has no output signal and the second switching device is turned on to realize the discharge of the residual voltage in the circuit. As for the control manner of the third switching device 22 on/off the first switching device 31 and on/off the second switching device 32, depending on the types of the first and second switching devices (NMOS, PMOS, NPN, PNP, etc.) selected, a person skilled in the art can select a corresponding suitable device type and output manner thereof for the third switching device 22, thereby selecting the output control manner of the switching control module for the third switching device 22 at the time of different signal inputs. As will be described later in connection with specific device type examples.

Further, the third switching device 22 may turn on or off the first switching device 31 and the second switching device 32 by corresponding circuit structures.

Specifically, the corresponding circuit structure of the first switching device 31 is a voltage dividing circuit (referred to as a second voltage dividing circuit) configured to make the first switching device 31 conductive when the third switching device 22 is conductive.

For example, the second voltage dividing circuit may include series resistors R3, R5 having one end connected to the power supply 33 and the other end grounded through the third switching device 22. Wherein the connection terminals of two of the series resistors are connected to the control terminal of the first switching device 31. Reference is made to the following description of fig. 3 for a specific circuit configuration, which shows a circuit diagram of an embodiment of the present utility model.

The corresponding circuit structure of the second switching device 32 is configured such that the second switching device 32 is turned on when the third switching device 22 is turned off.

For example, the circuit structure includes series R3, R5, R7, and resistor R8. The connection relationship between the resistors R3 and R5 is described above, and will not be described here again. One end of the resistor R7 is connected to one end of the third switching device 22 connected to the control end of the first switching device 31, and to the control end of the second switching device 32, and the other end is connected to GND. One end of the resistor R8 is connected to the circuit output terminal, and the other end is grounded through the second switching device 32. That is, the second switching device 32 is connected to the control terminal of the first switching device 31, and is connected to the output terminal through the resistor R8. For a specific circuit configuration, reference is made to the description below in connection with fig. 3.

It should be understood by those skilled in the art that the corresponding circuit structure of the first switching device 31 and the corresponding circuit structure of the second switching device 32 may also adopt other structures, as long as it is satisfied that when the third switching device 22 is turned on, the first switching device 31 is turned on and the second switching device 32 is turned off, and when the third switching device 22 is turned off, the first switching device 31 is turned off and the second switching device 32 is turned on.

In addition, in the circuit provided by the utility model, the first switching device and the second switching device of the output module can be complementary, namely, the first switching device and the second switching device can be field effect transistors or triodes with different polarities. The structure has high stability and strong anti-interference capability, and meanwhile, the static power consumption is lower.

In particular, the first switching device may be selected from one of a PMOS field effect transistor and an NMOS field effect transistor, and the second switching device may be selected from the other of a PMOS field effect transistor and an NMOS field effect transistor. In other words, when the first switching device is a PMOS transistor, the second switching device is an NMOS transistor; when the first switching device is an NMOS tube, the second switching device is a PMOS tube.

Alternatively, the first switching device is selected from one of a PNP type triode and an NPN type triode, and the second switching device is selected from the other.

The third switching device may be a MOS field effect transistor or a transistor.

For the selection of each switching device in the circuit provided by the utility model, those skilled in the art can understand that the first, second and third switching devices in the utility model can be MOS transistors, alternatively, can also be triodes. These switching devices may be the same type of switching device, for example all MOS transistors, or all transistors; alternatively, a part of the transistors may be MOS transistors, and another part may be triode transistors. Regardless of the type of switching device, a person skilled in the art can adapt the respective structure of the above-described circuit according to the operating principle of the respective switching device.

Optionally, the short-circuit protection module 35 may perform short-circuit or overcurrent protection on the circuit through a protection device (preferably a triode, so as to adjust the magnitude of the current limit current), a current limit resistor and a current sampling resistor. For a specific circuit structure, reference may be made to a circuit diagram provided in accordance with an embodiment of the present utility model shown in fig. 3 hereinafter.

Further, the output module 30 may further include a soft start control module 36 to reduce the impact of the inrush current at the start-up moment on the power supply.

Specifically, the soft start control module 36 may include a capacitor, where one end of the capacitor is connected to the control terminal of the first switching device, and the other end of the capacitor is connected to the circuit output terminal. Thereby, the on-time of the first switching device can be increased, and the transient impact of the load on the power supply can be reduced.

Optionally, the output module 30 may further include a protection circuit formed by a diode, where an anode of the diode is connected to the first switching device 31 and a cathode of the diode is connected to the second switching device 32. Therefore, the unidirectional current circulation of the current can be ensured, and the current is prevented from flowing reversely from the signal output end, so that the power supply is prevented from being damaged.

The circuit provided in an embodiment of the present utility model will be specifically described below by taking the first switching device 31 as a PMOS transistor Q1, the second switching device 32 as an NMOS transistor Q2, the third switching device 22 as an NPN transistor T1, and the protection device as a PNP transistor T2 as an example.

Referring to fig. 3, one embodiment of the high side drive output circuit of the present utility model is shown. The circuit comprises a resistor R1/R2/R3/R4/R5/R7/R8, a sampling resistor R6, a capacitor C1, a triode T1/T2, a diode D1 and a MOS tube Q1/Q2.

IN this circuit, SIGNAL input 10 is a CONTROL-SIGNAL-IN port and SIGNAL output 40 is a Vout port. The switch control module 20 includes a voltage divider circuit formed by series resistors R1 and R2 and a transistor T1 as a third switching device 22. In this example, the triode T1 is NPN type, and the second voltage dividing circuit matched with it includes resistors R3 and R5.

The first switching device 31 in the output module 30 is a PMOS transistor Q1, and the power supply 33 connected thereto is VDD. The second switching device 32 is an NMOS transistor Q2 connected to the ground terminal 34 (GND).

As also shown in fig. 3, in one embodiment, the high-side drive output circuit includes a short-circuit protection module. The short-circuit protection module comprises a triode T2, a current limiting resistor R4 and a sampling resistor R6.

The connection relation and the corresponding function of each circuit device are described in detail below.

One end of the resistor R1 is connected with a SIGNAL input end (input SIGNAL is CONTROL-SIGNAL-IN), and the other end of the resistor R2 is connected with one end of the resistor and the base electrode of the triode T1. R1 functions to provide a base current limit for T1 when the CONTROL-SIGNAL-IN output is high.

As will be appreciated by those skilled in the art, for an NPN transistor, the current flowing through collector (c), base (b), emitter (e) is related to: lie=ib+ic, ic=β×ib. When Ube is more than 0.7V, namely the emitter junction voltage Ube is forward biased, the triode is conducted. When Ube is less than 0.7V, namely the emitter junction voltage Ube is reversely biased, the triode is in a cut-off state, which is equivalent to the disconnection of the switch. The on-voltage and other parameters of the triode are determined by the specific device selected. Accordingly, the parameters of the voltage dividing circuit are also selected according to the specification requirements of the device, which is common knowledge of a person skilled in the art and will not be described in detail. Similarly, for PNP type triode, when Ube is less than-0.7V, the triode is conducted. When Ube > -0.7V, the transistor turns off. Likewise, specific circuit parameters need to be determined with reference to specifications of the selected transistor.

One end of the resistor R2 is connected with the base electrode of the triode T1 and one end of the resistor R1, and the other end of the resistor R2 is connected with GND. Two functions of R2 are that when the CONTROL-SIGNAL-IN is at high level, a series voltage dividing circuit is formed with R1 to provide the voltage required by the conduction of the triode T1; secondly, when the CONTROL-SIGNAL-IN is IN high resistance state/low level, the triode T1 is ensured to be IN a closed state.

One end of the resistor R3 is connected with one end of the collector of the triode T1 and one end of the resistor R7, and the other end of the resistor R3 is connected with the collector and the grid electrode of the triode T2, and the effect is that when a CONTROL SIGNAL CONTROL-SIGNAL-IN is at a high level, the triode T1 conducts the collector and the emitter to be connected with GND, the grid electrode of the triode Q1 consists of a voltage dividing circuit formed by resistors R3/R5/R6, and the resistance value of R3/R5 is set to enable the voltage value on R5 to be smaller than the |vgs (TH) | of the PMOS tube Q1 under the condition, so that Q1 is ensured to be opened; secondly, in order to prevent T1 or T2 from being burnt out when the triode T2 is started, a current limiting function is provided.

One end of the resistor R4 is connected with the base electrode of the triode T2, and the other end is connected with one end of the R5, the source electrode of the Q1 and one end of the R6. The function is to provide current limiting for the base of T2. When the current passing through R6 is overlarge and exceeds a certain value, the voltage drop on R6 exceeds 0.7V (triode on voltage), the base-emitter voltage Ube of T2 is larger than 0.7V, T2 is started according to the property of a triode, and R4 limits the current flowing through the base of T2 to prevent the current from being overlarge and burning T2.

One end of the resistor R5 is connected with the collector electrode of the triode T2, one end of the R3 and the grid electrode of the Q1, and the other end is connected with the end connected with the R4 and the R6. The function is to form partial pressure with R3 when the PMOS tube Q1 is normally opened. When T1 is turned on, R6/R5/R3 form a voltage divider circuit to provide a reliable gate-on voltage for Q1.

One end of the current sampling resistor R6 is directly connected with the emitter of the T2 and is connected with one end of the R4, the source electrode of the Q1 and one end of the R5. The function of this is to set the magnitude of the short-circuit current by detecting the voltage VR6 generated when R6 passes through the short-circuit.

One end of a resistor R7 is connected with the collector of the triode T1, one end of a resistor R3 and the grid of the Q2, and the other end of the resistor R7 is connected with GND, so that when the triode T1 is closed, a voltage dividing circuit is formed by the resistor R3/R5/R6, the grid voltage of the NMOS tube Q2 is larger than the Vgs (TH) voltage of the Q2, the Q2 is started, the grid voltage of the NMOS tube Q2 is prevented from exceeding the maximum value of the Vgs (TH) of the Q2, the Q2 is burnt, the residual voltage on the Vout is quickly connected to the GND through the resistors R8 and Q2, and the charge is discharged; another function is to ensure that the gate of Q2 is in an off state when T1 is on.

One end of the resistor R8 is connected with the drain electrode of the NMOS tube Q2, and the other end of the resistor R is connected with the negative electrode of the D1 to the Vout end. The NMOS transistor Q2 is connected with GND through the source electrode and the drain electrode of the NMOS transistor Q2 when the NMOS transistor Q2 is turned on, and the current limiting function of the output Vout on the GND is achieved.

One end of the capacitor C1 is connected with one end of R3, one end of T2 collector, one end of R5 and the grid electrode of the tube Q1, and the other end is connected with the anode of D1 and the drain electrode of Q1. The effect is that when the three-stage tube T1 is started, the conduction time of the PMOS tube Q1 is increased, and the instantaneous impact of the load on the power supply is reduced.

The positive pole of diode D1 links to each other with PMOS pipe Q1 drain electrode, electric capacity C1 one end, and the negative pole links to each other with resistance R8 one end and Vout. This serves to prevent damage to the VDD supply when Vout is shorted to other external supplies, which can be eliminated if VDD and the external shorted supply are equal.

The base electrode of the triode T1 is connected with one end of R1 and one end of R2, the emitter electrode is connected with GND, and the collector electrode is connected with one end of R3, one end of R7 and the grid electrode of Q2. When the CONTROL SIGNAL CONTROL-SIGNAL-IN is at high level, the voltage dividing circuit is formed by R3 and R5 by starting T1, so that the difference Vgs < Vgs (TH) between the gate voltage and the drain voltage of Q1 is satisfied, and the PMOS tube Q1 is opened.

The base electrode of the triode T2 is connected with one end of R4, the emitter electrode is connected with one end of a sampling resistor R6 to be connected with a power supply VDD, and the collector electrode is connected with one end of R3, one end of R5 and the grid electrode of Q1. The effect is that when the voltage drop of the resistor R6 is larger than 0.7V, namely when the current flowing through the Q1 is overlarge, T2 is started, the collector voltage of the T2 is equal to VDD, namely the grid voltage of the Q1 is equal to VDD, vgs=0 of the Q1, so that the PMOS tube Q1 is closed, and the purpose of protecting the Q1 is achieved.

The grid electrode of the PMOS tube Q1 is connected with one end of R3, one end of R5, one end of T2, one end of C1, the source electrode is connected with the other end of R5, one end of R4 and one end of R6, and the drain electrode is connected with the anode of D1 and the other end of C1. The function of the power supply circuit is to provide power supply output for the high-side driving circuit.

The grid electrode of the NMOS tube Q2 is connected with one end of R7, the collector electrode of T1 and one end of R3, the source electrode is connected with GND, and the drain electrode is connected with one end of R8. The effect is that when Q1 is off, Q2 is on, rapidly bleeding residual charge on the Vout output through resistor R8.

The MOS tube used in the scheme, such as Q1/Q2, can be replaced by a triode, and T1 can also be replaced by a MOS tube.

The specific principle of operation of the circuit in this embodiment is as follows:

1. when the Control-Signal-In outputs a high level to the subsequent stage (In particular, the Control-Signal-In may be an IO Control Signal of the MCU or a power supply voltage Signal), the T1 triode is turned on under the action of the voltage dividing circuit. Through the partial pressure action of R6, R5 and R3, vgs of Q1 is smaller than an opening threshold Vgs (TH), and Q1 is opened at the moment. At this time, the gate of Q2 is connected to GND through the collector of T1, and Vgs of Q2 is smaller than the on threshold Vgs (TH), so Q2 is in the off state, and Vout outputs voltage at this time, vout=vdd-0.7V-r6×iload, iload is load current.

When the circuit module or the peripheral connected with Vout has short circuit fault, the current flowing through the sampling resistor R6 is increased, the voltage drop on the R6 is increased, and when the voltage drop is larger than 0.7V, T2 is conducted, so that the grid voltage of Q1 is equal to the source voltage VDD, and Q1 is closed, thereby protecting Q1 from being damaged.

2. When the CONTROL-SIGNAL-IN output is low, T1 is off and Q1 is also off; at this time, the voltage Vgs on the gate of the Q2 is larger than the starting voltage threshold Vgs (TH) of the Q2 by serially connecting and dividing resistors R6/R5/R3/R7, so that the Q2 is in an on state, the residual charges on the Vout line are rapidly released by the Vout through the resistors R8 and Q2, the Vout is rapidly reduced to 0V, and therefore the stable and reliable power supply state of the circuit module or the peripheral equipment during rapid power-on is ensured.

Those skilled in the art will appreciate that: for an NMOS tube, vg-Vs > Vgs (TH), wherein Vgs (TH) is a threshold voltage threshold of the MOS tube, namely, the pressure difference between a G electrode (grid electrode) and an S electrode (source electrode) is larger than a certain value, the MOS tube can be conducted, but the pressure difference cannot be too large, otherwise, the MOS tube can be burnt out. Wherein the turn-on voltage and other parameters need to be referenced to the associated specifications depending on the particular device selected. Similarly, for the PMOS tube, vg-Vs is smaller than Vgs (TH), namely the pressure difference between the G pole and the S pole is smaller than a certain value, and the MOS tube is conducted (for the PMOS tube, the Vgs (TH) is a negative value). Likewise, specific parameters require reference to the specifications of a particular device.

The utility model provides a high-side driving output circuit, which has the characteristics of wide applicability because the output is subjected to a short-circuit protection function and a rapid discharging function is realized, so that equipment connected with the circuit can not be influenced by switching on and off of a power supply.

In the description of the present specification, descriptions of the terms "one embodiment," "some embodiments," "examples," "some examples," or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

In the present utility model, the terms "connected," "connected," and the like are to be construed broadly, and for example, "connected" may be a fixed connection, a removable connection, or an integral connection; "coupled" may be directly coupled or indirectly coupled through intermediaries. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

Finally, it should be noted that the above embodiments are only intended to illustrate the technical solution of the utility model and are not limiting. Although the present utility model has been described in detail with reference to the embodiments, it should be understood by those skilled in the art that modifications and equivalents may be made thereto without departing from the spirit and scope of the present utility model, which is intended to be covered by the claims.

Claims

1. A high-side drive output circuit, comprising:

a signal input terminal for receiving an input signal, the input signal being in one of a high level, a low level or a high resistance state,

the output module further comprises a short-circuit protection module connected with the first switching device, and the short-circuit protection module turns off the first switching device when the current flowing through the first switching device exceeds a preset value;

the first switching device and the second switching device are controlled to be switched on and off by a switching control module according to the high level or low level state of the input signal, so that:

when the input signal is in a high level, the output module outputs a voltage signal which is the same as that of the power supply, when the input signal is converted from the high level to a low level or a high resistance state, the output module does not output a signal, and the high-side driving output circuit discharges through the conducted second switching device.

2. The high-side drive output circuit of claim 1, wherein the short-circuit protection module comprises a protection device, a current limiting resistor, and a current sampling resistor, the protection device being selected from the group consisting of a transistor.

3. The high-side drive output circuit according to claim 1, wherein the output module further comprises a soft start control module, one end of the soft start control module is connected with the control end of the first switching device, and the other end of the soft start control module is connected with the circuit output end.

4. The high side drive output circuit of claim 1, wherein the switch control module comprises a third switching device and a first voltage divider circuit.

5. The high-side drive output circuit according to claim 4, wherein the first voltage dividing circuit comprises a series resistor having one end connected to the signal input terminal and the other end grounded, wherein the connection terminals of two resistors in the series resistor are connected to the control terminal of the third switching device.

6. The high side drive output circuit of claim 5, wherein the third switching device is a transistor.

7. The high-side drive output circuit according to claim 4, wherein the third switching device turns on the first switching device through a second voltage dividing circuit.

8. The high-side drive output circuit according to claim 7, wherein the second voltage dividing circuit comprises a series resistor having one end connected to the power supply and the other end grounded through a third switching device, wherein the connection ends of two resistors in the series resistor are connected to the control end of the first switching device.

9. The high-side drive output circuit according to claim 7 or 8, wherein the first switching device, the second switching device and the third switching device are selected from a MOS field effect transistor or a triode, wherein the first switching device and the second switching device are complementary.

10. The high-side drive output circuit according to claim 9, wherein the third switching device is an NPN transistor, wherein an emitter of the third switching device is grounded, and a collector of the third switching device is connected to the second voltage dividing circuit.

11. The high side drive output circuit of claim 10, wherein the protection device is a PNP transistor, the first switching device is a PMOS field effect transistor, the second switching device is an NMOS field effect transistor,

the collector of the protection device is connected with the grid of the first switching device, the emitter of the protection device is connected with the power supply, the base of the protection device is connected with one end of the current limiting resistor, and the other end of the current limiting resistor is connected with the source of the first switching device and is connected with the power supply through the current sampling resistor;

and/or

The grid electrode of the second switching device is connected with the collector electrode of the third switching device and one end of a voltage dividing resistor, the other end of the voltage dividing resistor is grounded, and the drain electrode of the second switching device is connected with the output end through another resistor.

12. The high side drive output circuit of claim 3, wherein the soft start control module comprises a capacitor.

13. The high side drive output circuit of claim 1, wherein the output module further comprises a diode having an anode connected to the first switching device and a cathode connected to the second switching device.