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NiMH Charger 2-Cell Series Switched

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I'm trying to setup the DS2712 in 2-cell series switched with the attached schematic. I'm double checking wiring at the moment , but wanted to verify the schematic was correct.

My Q2 bjt is getting extremely hot and all my current is running back through the inductor and d1 in a loop.

Any help much appreciated!!
 

what is this a switch mode charger? what would be the current of the circuit? is this a fast charger? what would be the current value when it passes to the inductor? if its a fast charger then the transistor much need a higher current rating also you can increase the value of the base resistor of the Q2 to limit the current passing to the transistor.
 

Yea, its a switched mode charger with fast charge of 1 amp (precharge and maintenance charge at 250mA).

The transistors I'm using are straight from the specified part in the schematic in the datasheet and aren't getting exceedingly hot anymore.

I fixed some wiring issues so it matches the schematic now and I have LED indicating state but the batteries are discharging at 8mA rather than charging.
 

I got it charging briefly in fast charge but it seems to fault out after a moment of fast charge.

I believe its going to fault state because the Von - Voff > Vctst (page 12 on datasheet) . Anyone know if you can set the resistor smaller than specified 20k ohm from CTST pin to gnd?
 

thanks. I need the schematic.
 

Lemme know if you get it working.
Thanks.
 

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