Hello,
I've got a problem that's been plaguing this circuit for a while. I think the answer is some kind of circuit protection but I need to understand the problem.
The symptom is that the LM7805 5V regulator gets destroyed sometimes and then it reads a voltage just a few mV less than the input voltage, ~12V in this case. Once this happens I need to replace the regulator.
I'm not sure what causes this issue. Today I tied the PANEL_V and BATT_V nodes together and after that, I read the high voltage on the 7805 output pin.
I know that I need to add reverse connection protection. I've googled this but have not come up with an answer. So if anyone can point me at some good resources that would be appreciated.
Any ideas on what is amiss with this circuit and why I keep killing 7805's?
Thanks.
I've got a problem that's been plaguing this circuit for a while. I think the answer is some kind of circuit protection but I need to understand the problem.
The symptom is that the LM7805 5V regulator gets destroyed sometimes and then it reads a voltage just a few mV less than the input voltage, ~12V in this case. Once this happens I need to replace the regulator.
I'm not sure what causes this issue. Today I tied the PANEL_V and BATT_V nodes together and after that, I read the high voltage on the 7805 output pin.
I know that I need to add reverse connection protection. I've googled this but have not come up with an answer. So if anyone can point me at some good resources that would be appreciated.
Any ideas on what is amiss with this circuit and why I keep killing 7805's?
Thanks.
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