Quick story, this is a small, battery operated micro controller for a single motor load. There is 1.3V being lost between the battery and the motor and so the nominal voltage of the battery is 3.6V but if it is dropped to just 3.3V, the IC will initiate a slow shut down sequence probably thinking it is out of power and needs to maintain enough to turn on the charger transistor.
I went through most components trying to find voltage drop and this one SMD component came up on the radar because it is losing .8V. Now, if it is a diode, I get it, but if it is a transistor, that V drop is a bit excessive. My in circuit diode testing has not proven this to be a diode yet so I thought I would ask.
My thought is that the micro controller is monitoring the battery voltage and when the actual bat voltage is say 3.3V, it will think it is much lower and start shutting down. I really think there is either a leaky component or something with high resistance causing the controller to see lower voltage. Or I guess maybe the controller is bad. The IC is WAY too small to test without making some testing devices. Looking for the easy fix first.
URCH - I disconnected the load (motor) and the controller now outputs full battery voltage to the terminals. I am not yet sure what that is telling me. Current goes up, resistance increases? Motor load is excessive? the battery pack is 800mah, 3.6V and motor draw is 1.25A. I did inspect the motor for shorted commutator, etc and all looked real good.
I went through most components trying to find voltage drop and this one SMD component came up on the radar because it is losing .8V. Now, if it is a diode, I get it, but if it is a transistor, that V drop is a bit excessive. My in circuit diode testing has not proven this to be a diode yet so I thought I would ask.
My thought is that the micro controller is monitoring the battery voltage and when the actual bat voltage is say 3.3V, it will think it is much lower and start shutting down. I really think there is either a leaky component or something with high resistance causing the controller to see lower voltage. Or I guess maybe the controller is bad. The IC is WAY too small to test without making some testing devices. Looking for the easy fix first.
URCH - I disconnected the load (motor) and the controller now outputs full battery voltage to the terminals. I am not yet sure what that is telling me. Current goes up, resistance increases? Motor load is excessive? the battery pack is 800mah, 3.6V and motor draw is 1.25A. I did inspect the motor for shorted commutator, etc and all looked real good.
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