Does psoc have a voltage monitoring section which resets the controller when a voltage higher than vcc is detected?
To be device specific I'm using cy8c20546A-24pvxi.
Not sure of PSoC1, but PSoC3/5 do have a low/high voltage monitor system that resets the part when voltage exceeds threshold limit.
PSOC 1 has a LVD detect.
This might help - http://www.psocdeveloper.com/uploads/tx_piapappnote/an2040.pdf