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Cutoff Load while charging the Lipo battery

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Johnny101

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I want to cutoff the battery from load, while charging it. Schematic of the designed circuit is attached. I have used a PNP transistor to do it. Positive terminal of the battery is connected to emitter, charger positive input is connected to base. Simulation is running good but I want to know would this circuit work in hardware? Is there any problem with the circuit?
 

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Audioguru

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The Schottky diode forward voltage drop will reduce the voltage to the battery resulting in not full charging.
The base resistor value is too high causing the transistor not to saturate since the datasheet shows it saturating well when its base current is 1/10th its collector current.
 

Johnny101

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Exactly, I am facing the problem of Schottky diode forward voltage drop in the hardware. What can be used instead of Schottky diode? Or any other technique you would recommend to cutoff the load while charging the battery?
 

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Use a charging jack with a switched contact on it. When the charging cord is plugged into the jack then the switched contact disconnects the load.
Some charger ICs have a charging output and another output that powers the load separately.
 

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