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Look at the circuit diagram. The positive of the battery is only connected through a capacitor. How can a capacitor possibly pass DC current to allow the battery to charge?Can anyone explain how this battery charger works?
Feb 13, 2022
Last reply: 4 years ago
5 Replies
What else might that yellow thing be, other than a capacitor?
A thermistor or a VDR, to provide current limiting. Regarding operation, power diodes tend to have a higher Vf than small signal diodes or transistor junctions, so once the diode goes into conduction it produces a large enough voltage to turn on the transistor and the red LED, indicating that charging is taking place. The green LED merely indicates that power is applied to the circuit.
My (probably futile) hope was that he might answer it himself, or at least try to...
Sorry, I should have checked the provenance of the thread more carefully. Apart from that, I couldn't resist the chance to show off. :-)
My guess - a polyfuse?
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