I copied this schematic off of an ATX power supply, it's the stand-by circuit.
The transformer is a 1 primary, 1 feedback on the same side and one center tapped secondary.(I didn't have the right symbol in my program so I stuck two together)
Only other thing I notice was on the board they had a spot of a resistor going for the emitter of 2SC3150 to base of 2SC945. Any ideas what that mite of been for?
The transformer is a 1 primary, 1 feedback on the same side and one center tapped secondary.(I didn't have the right symbol in my program so I stuck two together)
Only other thing I notice was on the board they had a spot of a resistor going for the emitter of 2SC3150 to base of 2SC945. Any ideas what that mite of been for?
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Someone might comment on this if you show the transformer inductances or turns ratios. Further, the 103 and 151 caps don't make sense.
151 is 15 +1 zero (0) so 150pF
103 is 10 +3 zero (0) so .010uF or 10nF
transformer inductance is: Feedback is 5.5uH, Primary is 4.42mH
btw most ceramic disc capacitors have the marking like 104, 103 things like that just in case you weren't sure.
103 is 10 +3 zero (0) so .010uF or 10nF
transformer inductance is: Feedback is 5.5uH, Primary is 4.42mH
btw most ceramic disc capacitors have the marking like 104, 103 things like that just in case you weren't sure.
It looks like a self-oscillating switcher, not very efficient but cheap. I've seen a 25-watter using that scheme.
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