Hi,
I have problems with my alpine.
I fixed the amp all working, then accidently probeb something, on the psu part.
so disconnected the output section, so only psu connected.
Now i can regulate postive 49.5v no problem, but minus stays on 46 v, nothing happens when i turn the potentiometer.
Measured on all zeners and checked the small sot23 transistors, nothinging seems to be wrong.
Any one who have any ide where to look. ?
I have problems with my alpine.
I fixed the amp all working, then accidently probeb something, on the psu part.
so disconnected the output section, so only psu connected.
Now i can regulate postive 49.5v no problem, but minus stays on 46 v, nothing happens when i turn the potentiometer.
Measured on all zeners and checked the small sot23 transistors, nothinging seems to be wrong.
Any one who have any ide where to look. ?
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Did you check ALL of the gate drives on the bad side?
The drive is square because it's still trying to reach the target output voltage. The good side drive duty cycle is reduced because it has reached the target rail voltage.
Is the amplitude on both secondary windings of both transformers equal in amplitude?
The drive is square because it's still trying to reach the target output voltage. The good side drive duty cycle is reduced because it has reached the target rail voltage.
Is the amplitude on both secondary windings of both transformers equal in amplitude?
it was very strange because the amp was working first last week, shorted something on the postitiv rail. the minus rail was lowered by 6 volts.... I took of mosfet and replaced with new pairs, but stil the same, it looked the same before the transformer but was little off on the secondary side.
I then swapped the transformers , measured with inductance meter, all the same.
Then took some windings off and checked put som new isolation tape and then put back inn.
also got this blinking low volt, so replaced the opamp, with 5532 and now it works.
Voila.... it works on both sides... Now regulated 49.5 volts.
thanks for help Perry.
best regards Niklas.
I then swapped the transformers , measured with inductance meter, all the same.
Then took some windings off and checked put som new isolation tape and then put back inn.
also got this blinking low volt, so replaced the opamp, with 5532 and now it works.
Voila.... it works on both sides... Now regulated 49.5 volts.
thanks for help Perry.
best regards Niklas.