CN212183500U - Multifunctional protection circuit of semiconductor device - Google Patents
Multifunctional protection circuit of semiconductor device Download PDFInfo
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- CN212183500U CN212183500U CN202020800834.1U CN202020800834U CN212183500U CN 212183500 U CN212183500 U CN 212183500U CN 202020800834 U CN202020800834 U CN 202020800834U CN 212183500 U CN212183500 U CN 212183500U
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Abstract
The utility model discloses a multifunctional protection circuit of a semiconductor device, which comprises a temperature monitoring module, a current monitoring module, a voltage monitoring module and a protection and fault display module; the output ends of the temperature monitoring module, the current monitoring module and the voltage monitoring module are directly connected with the input end of the protection and fault display module, so that the semiconductor power device can be protected when the semiconductor power device is over-temperature, over-current or over-voltage, and fault signals are output in a centralized mode. The multifunctional protection circuit is simple in hardware structure, comprehensively protects the semiconductor device, outputs a fault signal, and improves reliability and human-computer interaction.
Description
Technical Field
The utility model relates to a semiconductor device's multi-functional protection circuit especially relates to a semiconductor power device's circuit of excess temperature, overcurrent and overvoltage protection.
Background
At present, semiconductor power devices are widely applied to various electrical equipment and often work under severe weather and complex electrical conditions, so for power devices without built-in protection functions, when peripheral circuits of the power devices are designed, protection circuits must be added to ensure reliable operation of the power devices. Common types of protection circuits include overvoltage protection, overcurrent protection, over-temperature protection, overload protection, and the like.
The existing semiconductor power device protection circuit has two design modes as follows: 1. the single protection circuit is arranged, if only the overvoltage protection circuit is arranged, although the design can reduce the circuit complexity and the whole machine cost, the power device can possibly generate damage factors under extremely special use conditions, and components cannot be reliably protected, so that the equipment reliability is greatly reduced. 2. A plurality of independent protection circuits are arranged, and because the protection circuits are independently arranged, a plurality of sets of 'repeated' protection modules are needed, so that design resources are greatly wasted, and unnecessary cost is increased.
In addition, the two design modes only design a protection function, so that inspection personnel cannot know the circuit abnormal condition in time, the generation and elimination of faults cannot be monitored, and the equipment reliability is greatly reduced.
SUMMERY OF THE UTILITY MODEL
In order to solve the problem, the utility model discloses a simple structure protects and just with fault signal output's semiconductor power device's protection circuit to excess temperature, overcurrent and excessive pressure simultaneously.
According to an aspect of the embodiments of the present invention, there is provided a multifunctional protection circuit of a semiconductor device, including a temperature monitoring module, a current monitoring module, a voltage monitoring module, and a protection and fault display module, wherein an output terminal of the temperature monitoring module, an output terminal of the current monitoring module, and an output terminal of the voltage monitoring module are directly connected to an input terminal of the protection and fault display module.
Preferably, the temperature monitoring module comprises a first reference power supply VCC1, a thermistor, a first resistor R1, and a first diode D1; wherein the thermistor is required to be fastened with the semiconductor device shell; one end of the thermistor is connected to the ground, the other end of the thermistor is connected to the anode of the first diode D1 and one end of the first resistor R1, the other end of the first resistor R1 is connected to the reference power source VCC1, and the cathode of the first diode D1 is connected to the protection terminal.
Preferably, the voltage monitoring module comprises an eighth resistor R8, a third resistor R3, and a second diode D2; one end of the eighth resistor R8 is connected to the control terminal of the semiconductor device, the other end is connected to the anode of the second diode D2 and one end of the third resistor R3, the other end of the third resistor R3 is grounded, and the cathode of the second diode D2 is connected to the protection terminal.
Preferably, the current monitoring module includes a sampling resistor Rs, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a second reference power source VCC2, a first amplifier U1, and a third diode D3; wherein the sampling resistor Rs is connected between the negative electrode VIN-of the input end and the ground; a second reference power supply VCC2 supplies power to the first amplifier U1; one end of the fourth resistor R4 is connected to the ground, the other end of the fourth resistor R4 is connected to the inverting input terminal of the first amplifier U1 and one end of the sixth resistor R6, and the other end of the sixth resistor R6 is connected to the output terminal of the first amplifier U1; one end of the fifth resistor R5 is connected with the negative electrode VIN-of the input end, the other end of the fifth resistor R5 is connected with the equidirectional input end of the first amplifier U1 and one end of the seventh resistor R7, and the other end of the seventh resistor R7 is grounded; the output end of the first amplifier U1 is connected with the anode of the third diode D3, and the cathode of the third diode D3 is connected with the protection end.
Preferably, the protection and fault display module includes a first reference power VCC1, a third reference power VCC3, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a comparator U2, and a first capacitor C1; the third reference power source VCC3 supplies power to the comparator U2; one end of the ninth resistor R9 is connected with the protection end, and the other end is connected with the input end of the comparator U2; one end of a tenth resistor R10 is connected with the first reference power VCC1, the other end of the tenth resistor R10 is connected with the input end of the comparator U2 and one end of an eleventh resistor R11, and the other end of the eleventh resistor R11 is grounded; one end of a twelfth resistor R12 is connected with the output end of the comparator U2 and one end of a thirteenth resistor R13, and the other end of the twelfth resistor R12 is connected with a first reference power supply VCC 1; the other end of the thirteenth resistor R13 is connected with one end of the first capacitor C1; the other terminal of the first capacitor C1 is connected to ground.
Preferably, the semiconductor device may be an IGBT, an IPM, a MOSFET, a rectifier bridge, a diode, or a power chip.
Preferably, the thermistor is a positive temperature coefficient thermistor or a negative temperature coefficient thermistor.
Preferably, the protection terminal is connectable to the comparator common input terminal or the inverting input terminal via a ninth resistor R9.
Preferably, the non-grounded end of the first capacitor C1 is connected to a driving circuit of a DSP or a semiconductor device.
The utility model has the advantages that:
the circuit protection circuit 1 can carry out all-around protection on a semiconductor power device circuit, namely overvoltage protection, overcurrent protection and over-temperature protection.
2 the temperature monitoring module, the voltage monitoring module and the current monitoring module share one set of protection and fault display module, the circuit structure is simple, and the expenditure is saved.
3 when the protection circuit works, the fault signal is transmitted to the lower computer or the upper computer, so that fault processing can be carried out at the first time, and the reliability and the man-machine interaction of the circuit are improved.
4, the protection information is converted into an analog electric signal, and the analog electric signal is compared with a comparator, so that the trigger is reliable and basically free from false trigger.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It should be apparent that the drawings in the following description are merely exemplary, and that other embodiments can be derived from the drawings provided by those of ordinary skill in the art without inventive effort.
FIG. 1 is a schematic diagram of a main circuit of a semiconductor device and a temperature, voltage and current monitoring circuit according to the present embodiment;
fig. 2 is a protection and fault display circuit of the present embodiment.
Description of reference numerals:
100-a temperature monitoring module; 200-a current monitoring module; 300-voltage monitoring module.
Detailed Description
The present invention is described in terms of specific embodiments, and other advantages and benefits of the present invention will become apparent to those skilled in the art from the following disclosure. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
The invention will be further described with reference to the drawings and specific preferred embodiments without limiting the scope of the invention.
According to an aspect of an embodiment of the present invention, there is provided a semiconductor power device protection circuit, including a temperature monitoring module, a voltage monitoring module, a current monitoring module, and a protection and fault display module; the output ends of the temperature monitoring module, the current monitoring module and the voltage monitoring module are connected with the input end of the protection and fault display module; the multifunctional protection circuit can protect the semiconductor device when the semiconductor device is over-temperature, over-current or over-voltage, and can intensively output fault signals to a Digital Signal Processor (DSP).
Specifically, as shown in fig. 1, the main circuit is taken as an example of a booster circuit for analysis, and temperature, voltage, and current monitoring is performed on the semiconductor power device IGBT. Any other main circuit including a semiconductor power device may be the subject of study.
The temperature monitoring module 100 comprises a positive temperature coefficient thermistor Rptc, a voltage dividing resistor R1, a first diode D1 and a reference power supply VCC 1; wherein the positive temperature coefficient thermistor is fastened with the IGBT housingStarting; one end of the positive temperature coefficient thermistor is connected with the ground, the other end of the positive temperature coefficient thermistor is connected with the anode of a first diode D1, and the cathode of a first diode D1 is connected with the protection end; one end of the voltage dividing resistor R1 is connected with the reference power supply VCC1, and the other end is connected with the anode of the diode D1. Wherein, the temperature-resistance curve of the thermistor with positive temperature coefficient is consulted to obtain the resistance value Rp of the thermistor at the protection point temperature of the semiconductor device, and the R1 design needs to meet the requirement
Wherein VP is the comparator reference voltage and Vd is the diode turn-on voltage drop.
The current monitoring module 200 includes a sampling resistor Rs, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a second reference power VCC2, a first amplifier U1, and a third diode D3; one end of a sampling resistor Rs is connected with the ground, the other end of the sampling resistor Rs is connected with the negative electrode Vin & lt- & gt of the input end of the main circuit, one end of a resistor R4 is connected with the ground, and the other end of the resistor R4 is connected with the inverting input end of the amplifier; one end of a resistor R5 is connected with the negative electrode Vin-of the input end of the main circuit, the other end of the resistor R5 is connected with the non-inverting input end of the amplifier, one end of a resistor R6 is connected with the inverting input end of the amplifier, and the other end of the resistor R6 is connected with the output end of the amplifier; one end of the resistor R7 is connected with the non-inverting input end of the amplifier, and the other end is connected with the ground; the output end of the amplifier is connected with the anode of a third diode D3, and the cathode of the third diode is connected with the protection end. The amplifier may select READ2302 GSP. A sampling resistor Rs is connected between the input end and the ground, the collected weak voltage signal is used as an input to be amplified, and R4-R5 and R6-R7 can be set in the amplifying circuit, so that the amplification factor is R6/R4. And transmitting the amplified voltage signal to a comparator protection end. By means of the design of Rs and the amplification factor, the requirement that when the over-current IP is generated, the amplified voltage is the reference voltage VP of the comparator is met. Namely, it is
The voltage monitoring module 300 comprises an eighth resistor R8, a third resistor R3, and a second diode D2; wherein one end of the eighth resistor R8 is connected with the control terminal of the semiconductor device, and the other end is connected with the anode of the second diode D2The pole of the third resistor R3 is connected with one end of the third resistor R3, the other end of the third resistor R3 is grounded, and the cathode of the second diode D2 is connected with the protection end. Since the IGBT has the maximum voltage limit on the gate driving signal, R3 and R8 are designed to divide the voltage and output the gate voltage signal to the comparator protection terminal. The design of the divider resistor needs to meet the following requirements: the maximum grid voltage is Vgmax, which is required to satisfy
During actual design, the values of R8 and R3 are required to be far greater than R2, so that the voltage monitoring module is ensured not to influence the original circuit structure to the maximum extent.
As shown in fig. 2, the protection and fault display module includes a first reference power VCC1, a third reference power VCC3, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a comparator U2, and a first capacitor C1; the third reference power source VCC3 supplies power to the comparator U2; one end of the ninth resistor R9 is connected with the protection end, and the other end is connected with the input end of the comparator U2; one end of a tenth resistor R10 is connected with the first reference power VCC1, the other end of the tenth resistor R10 is connected with the input end of the comparator U2 and one end of an eleventh resistor R11, and the other end of the eleventh resistor R11 is grounded; one end of a twelfth resistor R12 is connected with the output end of the comparator U2 and one end of a thirteenth resistor R13, and the other end of the twelfth resistor R12 is connected with a first reference power supply VCC 1; the other end of the thirteenth resistor R13 is connected with one end of the first capacitor C1, and is connected to the DSP or a driving circuit of the power device for hardware shutdown of the device; the other terminal of the first capacitor C1 is connected to ground.
Because the three-way monitoring signal output ends are all connected with the diodes in series, the operation is equivalent to the OR operation of the three-way output potentials, and as long as one of the three-way monitoring signal output ends outputs a high level, the protection end outputs the high level. The output voltage of the protection terminal is compared with the reference voltage, as can be seen from FIG. 2, the reference voltage
When the Protect voltage is lower than the reference voltage, the comparator outputs a low level to the DSP; when the Protect voltage is higher than the reference voltage, the comparator outputs a high level to the DSP. DSP receptionAnd triggering a protection mode at a high level, and stopping the whole machine and reporting a fault. Wherein, R13 and C1 play a role in filtering.
For the parameter value selection, depending on the designed reference voltage VP, different values of VP will result in different resistance values. For example, VCC1 is 5V and VP is 2.5V. Then is represented by
R11 ═ R10 ═ 1K Ω; is composed of
D2 may be 1N4148 but is not limited to, R3 ═ 3k +200 Ω ═ 3.2k Ω, R8 ═ 10k Ω +6.8k Ω ═ 16.8k Ω default IGBT gate overvoltage 20V; is composed of
RS may be 0.01 Ω, R6 ═ R7 ═ 10k Ω, R4 ═ R5 ═ 1.5k +100 Ω ═ 1.6k Ω, and the overcurrent IP is assumed to be 40A; is composed of
Assuming that D1 is 1N4148, but not limited thereto, at the over-temperature point Rp is 1.8k Ω, R1 is 3k +200 Ω is 3.2k Ω. Amplifier selectable READ2302GSP is not limited to, and comparator selectable LM2903 is not limited to. In general, the model selection can be performed according to the corresponding relation, and no value limitation is caused on a single device, so that the flexibility is high.
Therefore, the utility model ensures that the inspector can find the abnormality of the power device at the first time by outputting the fault signals to the DSP chip in a centralized way; in addition, the output ends of the temperature monitoring module, the current monitoring module and the voltage monitoring module are connected to a protection end (Protect) together, and only one set of protection and fault display module is needed, so that the circuit structure is greatly simplified, and the cost is reduced; because the output ends of the three monitoring modules are all connected in seriesAnd when any one or more of the three monitoring modules outputs high level, the protection end outputs high level, namely, the protection end outputs signals or operation to the temperature monitoring module, the voltage monitoring module and the current monitoring module. Wherein, the temperature monitoring module monitors the surface temperature of the IGBT switch tube, and when the temperature of the semiconductor power device rises, a positive temperature coefficient thermistor (Resistance)Positive Temperature CoefficientFor short, Rptc) The resistance becomes large, the thermistor RptcThe divided voltage becomes large so that the protection terminal outputs a high level.
In the current monitoring module, the main circuit current is monitored and is passed through a sampling resistor (R)sampleFor short, Rs) The current signal is converted into a voltage signal, which is then amplified by an operational amplifier. When the current in the circuit is too large, the output voltage of the operational amplifier is at a high level, and the high level is output to the protection end through the diode.
In the voltage monitoring module, the gate voltage of the IGBT is monitored, and is divided by a resistor R3 and a resistor R8 and output to a protection terminal through a diode D2. When the grid voltage is too high, the resistor R3 divides the voltage value
It also becomes large to output a high level to the protection terminal.
In some embodiments, the device to be protected can be not only an IGBT, but also protection of IPM, MOSFET, rectifier bridge, diode, power chip, and the like; the to-be-measured value can be voltage, high temperature, low temperature, humidity, force, magnetic field, rotating speed, light intensity and the like, and different protection amount centralized control can be realized by matching with different sensors;
in some embodiments, the thermistor can be a positive temperature coefficient thermistor, and can also be a negative temperature coefficient thermistor;
in some embodiments, in the protection and fault display module, the reference voltage may be connected to the positive input end of the comparator, and may also be connected to the negative input end of the comparator;
in some embodiments, the comparator output signal may be connected to the DSP and also to the driver circuit of the power device.
Although the invention has been described in detail with respect to the general description and the specific embodiments, it will be apparent to those skilled in the art that modifications and improvements can be made based on the invention. Therefore, such modifications and improvements are intended to be within the scope of the invention as claimed.
Claims (9)
1. The multifunctional protection circuit of the semiconductor device comprises a temperature monitoring module, a current monitoring module, a voltage monitoring module and a protection and fault display module, and is characterized in that the output end of the temperature monitoring module, the output end of the current monitoring module and the output end of the voltage monitoring module are directly connected with the input end of the protection and fault display module.
2. The multifunctional protection circuit of a semiconductor device according to claim 1, wherein the temperature monitoring module comprises a first reference power VCC1, a thermistor, a first resistor R1, a first diode D1; wherein the thermistor is required to be fastened with the semiconductor device shell; one end of the thermistor is connected to the ground, the other end of the thermistor is connected to the anode of the first diode D1 and one end of the first resistor R1, the other end of the first resistor R1 is connected to the reference power source VCC1, and the cathode of the first diode D1 is connected to the protection terminal.
3. The multifunctional protection circuit of a semiconductor device as claimed in claim 1, wherein the voltage monitoring module comprises an eighth resistor R8, a third resistor R3, a second diode D2; one end of the eighth resistor R8 is connected to the control terminal of the semiconductor device, the other end is connected to the anode of the second diode D2 and one end of the third resistor R3, the other end of the third resistor R3 is grounded, and the cathode of the second diode D2 is connected to the protection terminal.
4. The multifunctional protection circuit of a semiconductor device as claimed in claim 1, wherein the current monitoring module comprises a sampling resistor Rs, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a second reference power source VCC2, a first amplifier U1, a third diode D3; wherein the sampling resistor Rs is connected between the negative electrode VIN-of the input end and the ground; a second reference power supply VCC2 supplies power to the first amplifier U1; one end of the fourth resistor R4 is connected to the ground, the other end of the fourth resistor R4 is connected to the inverting input terminal of the first amplifier U1 and one end of the sixth resistor R6, and the other end of the sixth resistor R6 is connected to the output terminal of the first amplifier U1; one end of the fifth resistor R5 is connected with the negative electrode VIN-of the input end, the other end of the fifth resistor R5 is connected with the equidirectional input end of the first amplifier U1 and one end of the seventh resistor R7, and the other end of the seventh resistor R7 is grounded; the output end of the first amplifier U1 is connected with the anode of the third diode D3, and the cathode of the third diode D3 is connected with the protection end.
5. The multifunctional protection circuit of a semiconductor device as claimed in claim 1, wherein the protection and fault display module comprises a first reference power VCC1, a third reference power VCC3, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a comparator U2, a first capacitor C1; the third reference power source VCC3 supplies power to the comparator U2; one end of the ninth resistor R9 is connected with the protection end, and the other end is connected with the input end of the comparator U2; one end of a tenth resistor R10 is connected with the first reference power VCC1, the other end of the tenth resistor R10 is connected with the input end of the comparator U2 and one end of an eleventh resistor R11, and the other end of the eleventh resistor R11 is grounded; one end of a twelfth resistor R12 is connected with the output end of the comparator U2 and one end of a thirteenth resistor R13, and the other end of the twelfth resistor R12 is connected with a first reference power supply VCC 1; the other end of the thirteenth resistor R13 is connected with one end of the first capacitor C1; the other terminal of the first capacitor C1 is connected to ground.
6. The multi-functional protection circuit of a semiconductor device according to claim 1, wherein the semiconductor device is an IGBT, an IPM, a MOSFET, a rectifier bridge, a diode, or a power chip.
7. The multifunctional protection circuit of a semiconductor device as claimed in claim 2, wherein the thermistor is a positive temperature coefficient thermistor or a negative temperature coefficient thermistor.
8. The multi-functional protection circuit of a semiconductor device as claimed in claim 5, wherein the protection terminal is connectable to a common input terminal or an inverting input terminal of the comparator through a ninth resistor R9.
9. The semiconductor device multifunctional protection circuit according to claim 5, wherein a non-grounded terminal of the first capacitor C1 is connected to a DSP or a driver circuit of the semiconductor device.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202020800834.1U CN212183500U (en) | 2020-05-14 | 2020-05-14 | Multifunctional protection circuit of semiconductor device |
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| CN202020800834.1U CN212183500U (en) | 2020-05-14 | 2020-05-14 | Multifunctional protection circuit of semiconductor device |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113689827A (en) * | 2021-08-30 | 2021-11-23 | 四川虹美智能科技有限公司 | Air conditioner wire controller |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113689827A (en) * | 2021-08-30 | 2021-11-23 | 四川虹美智能科技有限公司 | Air conditioner wire controller |
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Effective date of registration: 20221021 Address after: 315191 No. 1166 Mingguang North Road, Jiangshan Town, Ningbo, Zhejiang, Yinzhou District Patentee after: NINGBO AUX ELECTRIC Co.,Ltd. Patentee after: AUX AIR CONDITIONING LIMITED BY SHARE Ltd. Address before: 315191 No. 1166 Mingguang North Road, Jiangshan Town, Ningbo, Zhejiang, Yinzhou District Patentee before: NINGBO AUX ELECTRIC Co.,Ltd. Patentee before: Ningbo Oxfam intelligent commercial air conditioning manufacturing Co.,Ltd. |