I am working on below schematic:
+42VA is 42 V DC and +42VAO is also 42V DC when PNP Transistor Q1 is ON. When Q1 is ON, load on +42VAO is 10 mA max. OPTO used is P181.
But it is observed that Q1 (CXT3906) is getting damaged frequently.
I can see in datasheet that VCEO and VBEO max is 40V and VEBO is 5V. Is this main reason of Q1 failure?
Base is also connected to +42VA through R76(100K) and R77(100k), so for base maximum voltage which is the voltage I can check in datasheet?
Is there any reason for Q1 failure other than this OR how can I Improve it?
Thanks in advance.
Best Answer
The maximum collector emitter voltage for Q1 is 40V - read the data sheet - you are applying 42 volts.