I use this circuit to output a 12V square wave. Why does it always burn Q2? Why is this circuit unreasonable? Please help me analyze it, thank you.
Aurelius 发表于 February 1, 2021
The upper and lower tubes may be turned on at the same time.
Kennan 发表于 February 1, 2021
It is caused by the heavy load, and it is necessary to not replace the mid-power transistor.
Phyllis 发表于 February 1, 2021
The transistor is burnt out due to insufficient drive current. The transistor drive resistance is 10K. Assuming that the drive voltage is 12V at the initial resistance, 12V/10K=1.2mA, assuming that the transistor magnification is 100 times (not achieved under power conditions), that is 120mA, in the case of insufficient drive, the transistor is in a linear amplification state, and the power consumption is large. When the control frequency is high, the MOS also requires current and burns out due to heat.
