Please ask.
The above circuit CN2 is followed by a load, and the current is about 40mA. PB1 is connected to MCU IO port, R12 is connected to 1K resistor. When doing high temperature test on this circuit at 85℃, transistor Q1 burned out, BE junction burned out, and the load behind did not work. Various calculations should feel no problem, but It's broken, the attachment is the information of the transistor, please analyze the reason, thank you.
Sandy Posted on December 8, 2020
What is CN2? Relay?
Humberto Posted on December 8, 2020
If I am not wrong, did you design this circuit yourself? There is an error in principle, it is not surprising that it burned.
Santos Posted on December 8, 2020
What is the key to the load connection, how to output GND?