Semiconductor device

Abstract

Provided is a level shifting circuit capable of preventing a power device from a malfunction also when a dv/dt transient signal is supplied with time difference. A high-potential side power device driving circuit has a clock signal generation circuit generating the so-called internal clock signal by outputting a pulse in a constant cycle for driving NMOS transistors and an iterative pulse generation circuit monitoring the state of an external input signal in synchronization with an output signal of the clock signal generation circuit, receiving a pulsing input signal generated with reference to a ground potential and generating pulsing ON and OFF signals.

Description

technical field [0001] The present invention relates to a semiconductor device, especially a level shift circuit of a power device for preventing malfunction caused by a dv / dt transition signal. Background technique [0002] Figure 36 The structure of the level shift circuit 90 of a conventional power device is shown. Figure 36 The structure shown is disclosed in JP-A-9-200017. [0003] exist Figure 36 Among them, the power devices 12 and 13 such as IGBT (insulated bipolar transistor) are push-pull connected between the positive pole and the negative pole (ground potential GND) of the power supply PS to form a half-bridge power device. In addition, freewheeling diodes D1 and D2 are connected in parallel with power devices 12 and 13 in reverse direction, respectively. Furthermore, a load (inductive load such as a motor) 14 is connected to a connection point N1 between the power device 12 and the power device 13 . [0004] exist Figure 36 Among them, the power device 12 ...

AI Technical Summary

Problems solved by technology

[0024] However, although the protection circuit 8 functions as a filter when the false pulses caused by the dv / dt transition signal are simultaneously supplied as the signals S2 and S3, when the false pulses P1 and P2 caused by the dv / dt transition signal are caused by the HNMOS transistor 4 and When there is a time difference supply due to the deviation of the element characteristics of 5, in the output signals S6 and S7 of the protection circuit 8, pulse signals P11 and P12 with a width corresponding to the time difference are supplied, so that the power device 12 will be caused by the pulse signals P11 and P12. Misoperation in on-state or off-state

[0025] Moreover, when the power device 12 malfunctions, it will maintain the malfunction until the next normal ON signal or OFF signal is supplied. Depending on the situation, the power devices 12 and 13 may be short-circuited or the like.

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