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problem on capacitor of timer

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franticEB

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Hi i have this circuit on board that doesn't show problems:

wd.jpg

then the designers decided to add a 200nF capacitor on cv pin in order to obtain a soft start of pulse signal in input to mosfet.

wd.jpg

I noticed a problem: when the -12v (timer is fed with negative voltage) goes to 0 there is a supply hole (50V) of about 20ms as if it were a short circuit.
when the -12v goes to 0 in the same circuit but without the 200nF capacitor there is not problems.
-12V is generated with self-holding circuitry starting from the output of transformer in figure.

Anyone could help me please?
 

BradtheRad

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It is difficult to figure out which of the ground symbols is really zero ground.

This is an unusual arrangement of two power supplies.

A lot of things will become more clear if you redraw your schematic so all wires are connected to something, with no ground symbols.
 

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