Driving circuit for power semiconductor element

Abstract

To solve the problem that if a drive circuit for power semiconductor device is applied to an IGBT 1 high in breakdown voltage, diodes (5) high in the breakdown voltage must be connected in series in multiple stages, and this leads to an increase in the cost and degradation in reliability, short circuit detection by a collector voltage detection circuit (6) is significantly delayed, and the IGBT 1 cannot be protected sometimes. During a period for which a sampling circuit (16) permits detection of gate voltage Vge, the gate voltage Vge is detected. If the gate voltage Vge exceeds a reference value, an abnormality is recognized to have occurred in the IGBT 11.

Description

technical field [0001] The present invention relates to a driving circuit of a power semiconductor element for detecting an abnormality occurring in the power semiconductor element. Background technique [0002] Figure 24 It is a structural diagram showing a drive circuit of a conventional power semiconductor element. In the figure, 1 is an IGBT (Insulated Gate Bipolar Transistor) as a power semiconductor element, and 2 is a switch to switch IGBT1 when a conduction command is input from the outside. The gate command to the closed state is output to the buffer 3, and if the shut-off command is input from the outside, the gate command to transfer the IGBT1 to the open state is output to the control logic block of the buffer 3, and 3 is based on the slave control logic The gate command output by block 2 drives the buffer of IGBT1, 4a is the turn-on gate resistance, 4b is the turn-off gate resistance, 5 is the cathode connected to the collector of IGBT1, and the anode is connec...

AI Technical Summary

Problems solved by technology

For this reason, the short-circuit detection by the collector voltage detection circuit 6 is significantly delayed, and there is a problem that the IGBT1 may not be protected.

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