Hi All,
I'm trying to figure out what kind of film capacitor is pictured here (C121). I know its
220nF rated at 275 VAC. I'm limited to sizes 13mmx5mm or 13x6mm which narrows down my options on mouser to general purpose or power factor correction capacitors. I know I can find more information like used for EMI suppression by digging deeper in the data sheets. I don't know what their purpose is though, and they don't show the X2 rating. Are these capacitors "across-the-line"? Any help would be appreciated. Thanks and good day / evening.
I'm trying to figure out what kind of film capacitor is pictured here (C121). I know its
220nF rated at 275 VAC. I'm limited to sizes 13mmx5mm or 13x6mm which narrows down my options on mouser to general purpose or power factor correction capacitors. I know I can find more information like used for EMI suppression by digging deeper in the data sheets. I don't know what their purpose is though, and they don't show the X2 rating. Are these capacitors "across-the-line"? Any help would be appreciated. Thanks and good day / evening.
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It doesn't need an X2 rating. It's between two DC supplies. The AC rating isn't important either, only the DC rating.
Ok, is it used to reduce AC noise? Would this capacitor be a good fit?
B32671P5224K000 EPCOS / TDK | Mouser
Thanks
B32671P5224K000 EPCOS / TDK | Mouser
Thanks
Ah, correction - I do not know it is 275 VAC, the capacitor reads 250V, I'm now guessing thats 250 VDC. I know the voltage rails are +/- 55 Volts.
It´s filtering rail noise and probably compensating some positive going waveform on positive rail coupling it to a similar one but opposite polarity in the negative one.
That TDK one is a polyprop (MKP) and should be fine even though the one you are replacing could be a polyester (MKT) which some argue have a slightly different sonic signature.
Generally these type of caps last forever in relative terms so unless it's physically broken the one you have is probably still doing exactly what it was intended to do when the amp was designed.
Generally these type of caps last forever in relative terms so unless it's physically broken the one you have is probably still doing exactly what it was intended to do when the amp was designed.
Thanks for the help. I’ll leave these capacitors be, I don’t see or measure any sign if damage. The amp is working...
Or that the designers taken the advice of D.Self --taken from his part 3 of his selecting the right operational amp.
Direct quote from Douglas-
The 5532 and 5534 type op-amps require adequate supply decoupling if they are to remain stable, otherwise they appear to be subject to some sort of internal oscillation that degrades linearity without being visible on a normal oscilloscope. The essential requirement is that the positive and negative rails should be decoupled with a 100 nF capacitor between them, at a distance of not more than a few millimeters from the op-amp; normally one such capacitor is fitted per package as close to it as possible.
It is not necessary, and often not desirable, to have two capacitors going to ground; every capacitor between a supply rail and ground carries the risk of injecting rail noise into the ground.'
Somebody must read his instruction on audio power amplifier design books I got it all in stages over the years in EW.
Acknowledgement given that the quote belong to D.self.
Direct quote from Douglas-
The 5532 and 5534 type op-amps require adequate supply decoupling if they are to remain stable, otherwise they appear to be subject to some sort of internal oscillation that degrades linearity without being visible on a normal oscilloscope. The essential requirement is that the positive and negative rails should be decoupled with a 100 nF capacitor between them, at a distance of not more than a few millimeters from the op-amp; normally one such capacitor is fitted per package as close to it as possible.
It is not necessary, and often not desirable, to have two capacitors going to ground; every capacitor between a supply rail and ground carries the risk of injecting rail noise into the ground.'
Somebody must read his instruction on audio power amplifier design books I got it all in stages over the years in EW.
Acknowledgement given that the quote belong to D.self.