There is a leakage cap in the circuit, when I turned off the power switch then vcc slowly dropped down and not all the way to zero voltage on the scope compare to the good one it's promtly dropped to zero. I need help, is there any ideas out there? BTW, I tried to removed all the caps related to the Vcc, but still having the same problem???

 

What circuit are you talking about?

 

It would help a great deal if you posted a schematic of the circuit.

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