Hi, I'm a noob with electronics attempting to fix a battery charger circuit, the old transistor on the circuit is fried beyond recognition, no model numbers any more. I dont know what to replace with..
The battery is backup power for a freezer, just so it can provide an alarm state if theres no power.
Battery went flat, the charge leads have no voltage, a transistor is destroyed.
Leg 1 (left) goes to an OP amp IC output amongst othwer things, Leg 3 (right) goes to the same OP amp IC, but input. It also parallel with 6 other larger ICs that I havent checked yet (hard to desolder). Leg 2 (middle) has a series connected resistor, looks like a 1 watt, 15 ohm, looks to be linked into the positive rail, close downline from a recitifier IC. (I'm assuming thats gate, so when power comes on transistor switches on the 5V signal??) Meaning I sdhould be looking at a PNP transistor??
I'm not familiar with this schematic and havent worked with transistors before, does anyone have an idea of how tghis circuit should function and what transistor I should look into?
Many thanks!
The battery is backup power for a freezer, just so it can provide an alarm state if theres no power.
Battery went flat, the charge leads have no voltage, a transistor is destroyed.
Leg 1 (left) goes to an OP amp IC output amongst othwer things, Leg 3 (right) goes to the same OP amp IC, but input. It also parallel with 6 other larger ICs that I havent checked yet (hard to desolder). Leg 2 (middle) has a series connected resistor, looks like a 1 watt, 15 ohm, looks to be linked into the positive rail, close downline from a recitifier IC. (I'm assuming thats gate, so when power comes on transistor switches on the 5V signal??) Meaning I sdhould be looking at a PNP transistor??
I'm not familiar with this schematic and havent worked with transistors before, does anyone have an idea of how tghis circuit should function and what transistor I should look into?
Many thanks!