Circuit structure for protecting driving tube

Abstract

The invention provides a circuit structure for protecting a driving tube. The circuit structure comprises a buffer for buffering driving signals, a first resistor of which one end is connected with the buffer, and a gate driver of which an input end is connected with the other end of the first resistor, wherein the gate driver is used for driving the driving tube according to the driving signals from the buffer through the first resistor. The circuit structure also comprises a voltage limiting element arranged between the buffer and the first resistor, and a discharge element of which one endis connected between the voltage limiting element and the first resistor and the other end is earthed. The circuit structure can reduce the excessive heat and even damage of a power tube caused by false conduction under the condition of interference to play a role in prolonging the service life of the power tube.

Description

technical field [0001] The invention relates to the field of high-power MOSFET and IGBT driving circuits, in particular to a circuit structure for protecting a driving tube (such as an IGBT driving tube). Background technique [0002] The maintenance link plays an extremely important role in the PDP color gray scale display. The gray scale is realized by adding different sustain pulses. In the actual process, the sustain pulses of each subfield are different. Through The control signal controls the high-power IGBT to realize the switching of the IGBT, so that the Vs voltage is added to the screen according to the requirements of the control signal. But in the implementation process, such as figure 1 As shown, due to the unreasonable wiring, the ground with large current and the ground with small current of control signal crosstalk each other, which makes the control waveform distorted, as shown in image 3 As shown, the SUSH and SUSL switches are misconducted, the image is...

AI Technical Summary

Problems solved by technology

But in the implementation process, such as figure 1 As shown, due to unreasonable wiring, the ground with high current and the ground with small current of control signal crosstalk each other, which makes the control waveform distorted, as shown in image 3 As shown, the SUSH and SUSL switches will be misconducted, the image will deteriorate, the power consumption of the switch tube will increase, and even the switch tube will be burned. This phenomenon is more obvious when the grounding resistance is large.

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