CN204314429U

CN204314429U - A kind of IGBT defencive function testing circuit

Info

Publication number: CN204314429U
Application number: CN201420813819.5U
Authority: CN
Inventors: 边成登; 刘林; 王有利; 潘传杰; 汪中霞
Original assignee: GLORYMV ELECTRONICS CO Ltd
Current assignee: GLORYMV ELECTRONICS CO Ltd
Priority date: 2014-12-19
Filing date: 2014-12-19
Publication date: 2015-05-06
Anticipated expiration: 2024-12-19

Abstract

The utility model discloses a kind of IGBT defencive function testing circuit; the pulse signal that trigger source N1 produces is divided into two-way; one tunnel is delivered to field effect transistor V1 grid through delay circuit N2, shaping circuit N4; another road is delivered to the G pole of IGBT through shaping circuit N3, driver module N5; the C pole of described IGBT connects the source electrode of field effect transistor V1; E pole ground connection, the drain electrode of described field effect transistor V1 meets VCC.The utility model adopts simple circuit form; little circuit component; the operating time of protection of driver module for over current fault can be tested out fast and accurately; with low cost; successful; there is no and damage the risk of IGBT own, and there is versatility, be applicable to IGBT and the driver module of various brand and model.

Description

A kind of IGBT defencive function testing circuit

Technical field

The utility model relates to testing circuit field, particularly relates to a kind of for detecting the test circuit of driver module for IGBT over current fault guard time.

Background technology

Along with the progress of science and technology, IGBT module is widely used in all trades and professions with its superior performance.In its operational process, one of main source of damage is overcurrent damage, and the electric current that namely during its conducting, C, E flow through at the two poles of the earth is too high and damage.As long as and when there is excess current at the time internal cutting off drive singal of IGBT vendors dictate; reducing On current would not cause IGBT to damage because of overcurrent; although so various informative for the driver module of control IGBT; manufacturer is numerous; but the defencive function be all integrated with in nearly all driver module for overcurrent fault; its C, E end tube voltage drop can zooming principle when overcurrent occurs for application IGBT, realizes fault handling.Because there is very high requirement the response time for IGBT current foldback circuit; IGBT drive module manufacturer generally can provide its general parameter; but the difference of IGBT and driver module monomer and peripheral circuit postpone, the difference of application demand parameter; all can cause this Parameters variation; so need to carry out independent test just can obtain parameter accurately, the operation that guarantee IGBT is reliable and stable for often organizing IGBT drive module.

Traditional detection method sets up peripheral circuit directly to make IGBT occur overcurrent condition, Test driver guard time.Although this kind of method is effective, if the improper IGBT that just can cause of protection circuit parameter damages, cause very large economic loss.

Utility model content

Technical problem to be solved in the utility model is the testing circuit realizing a kind of overcurrent protection actuation time that can test out driver module reality fast and accurately.

To achieve these goals; the technical solution adopted in the utility model is: a kind of IGBT defencive function testing circuit; the pulse signal that trigger source N1 produces is divided into two-way; one tunnel is delivered to field effect transistor V1 grid through delay circuit N2, shaping circuit N4; another road is delivered to the G pole of IGBT through shaping circuit N3, driver module N5; the C pole of described IGBT connects the source electrode of field effect transistor V1, and E pole ground connection, the drain electrode of described field effect transistor V1 meets VCC.

Described connecing between the source electrode of field effect transistor V1 and drain electrode is connected with electric capacity C1, and the drain electrode of described field effect transistor V1 meets VCC through resistance RP1.

Described trigger source N1 is crystal oscillator source.

The utility model adopts simple circuit form; little circuit component; the operating time of protection of driver module for over current fault can be tested out fast and accurately; with low cost; successful; there is no and damage the risk of IGBT own, and there is versatility, be applicable to IGBT and the driver module of various brand and model.

Accompanying drawing explanation

Below to the content brief description that width accompanying drawing every in the utility model instructions is expressed:

Fig. 1 is schematic block circuit diagram of the present utility model;

Fig. 2 is test sequence figure.

Embodiment

Utilize crystal oscillator as signal trigger source N1, the pulse signal produced is divided into two-way, as shown in Figure 1, one tunnel is through shaping circuit N3 (as shaping pulse), driver module N5 is delivered to the G pole of IGBT, driver module is as detection pulse signal and using signal as driving enable signal, another road is through delay circuit N2, shaping circuit N4 (as shaping pulse) is delivered to field effect transistor V1 grid, the C pole of IGBT connects the source electrode of field effect transistor V1, E pole ground connection, the drain electrode of field effect transistor V1 meets VCC, the pulse signal being input to field effect transistor V1 grid controls field effect transistor V1 and turns off, thus make the C pole tension moment lifting being connected on the IGBT on field effect transistor V1 source electrode, the tube voltage drop moment rising condition occurred when simulating IGBT overcurrent, thus test I GBT drive waveforms obtains the response time of surveyed driver module for overcurrent protection fast and accurately.

Connect between the source electrode of field effect transistor V1 and drain electrode and be connected with electric capacity C1, the drain electrode of field effect transistor V1 meets VCC through resistance RP1, wherein field effect transistor V1, resistance RP1, electric capacity C1 are common electronics element, have no special requirements, and only need to select corresponding voltage withstand class according to external power supply.Crystal oscillator clock circuit N1 is conventional crystal oscillator source, and delay circuit N2, shaping circuit N3 and shaping circuit N4 all can use conventional monostalbe trigger chip to realize.

The utility model testing circuit principle of work is as follows: when this circuit powers beginning, field effect transistor V1 is in conducting state by the control of shaping circuit N4.Now crystal oscillator trigger source N1 circuit starts to send trigger pulse, and shaping circuit N3 is delivered on a road, after N3 shaping, delivers to driver module signal input part to be detected, as IGBT source driving signal.Delay circuit N2 is delivered on an other road, by this signal delay certain hour, can ensure the signal that this signal lag exports in shaping circuit N3 like this, thus after ensureing that this signal is in IGBT driving conducting.The output signal of delay circuit N2 enters shaping circuit N4, its output signal controls field effect transistor V1 and turns off, the rapid lifting of drain potential of field effect transistor V1, and utilize the principle that electric capacity both end voltage can not be suddenlyd change, the current potential also lifting rapidly at electric capacity C1 two ends, cause the C electrode potential of IGBT to raise rapidly, thus simulate the situation that tube voltage drop that IGBT occurs when there is overcurrent situations raises rapidly.Now use the oscilloprobe C pole waveform of test I GBT and the output drive waveforms (illustrating see Fig. 2) of driver module respectively, contrast accurately can measure IGBT drive module, and after there is overcurrent fault, it protects response time.

Above by reference to the accompanying drawings to invention has been exemplary description; obvious the utility model specific implementation is not subject to the restrictions described above; as long as have employed the improvement of the various unsubstantialities that method of the present invention is conceived and technical scheme is carried out; or design of the present invention and technical scheme directly applied to other occasion, all within protection domain of the present utility model without to improve.

Claims

1. an IGBT defencive function testing circuit; it is characterized in that: the pulse signal that trigger source N1 produces is divided into two-way; one tunnel is delivered to field effect transistor V1 grid through delay circuit N2, shaping circuit N4; another road is delivered to the G pole of IGBT through shaping circuit N3, driver module N5; the C pole of described IGBT connects the source electrode of field effect transistor V1; E pole ground connection, the drain electrode of described field effect transistor V1 meets VCC.

2. IGBT defencive function testing circuit according to claim 1, is characterized in that: described in connect field effect transistor V1 source electrode and drain electrode between be connected with electric capacity C1, the drain electrode of described field effect transistor V1 meets VCC through resistance RP1.

3. IGBT defencive function testing circuit according to claim 1 and 2, is characterized in that: described trigger source N1 is crystal oscillator source.