BQ25173: Leakage Question

Hello

The BQ25173 OUT pin will very low leakage current, 350nA typical.  

But the Voltage divider for FB pin will draw additional current and FB pin itself will also draw current.  

If very low leakage current is needed the Voltage divider network and FB pin need to be disconnected.  We have an applications circuit that will do this.

Hi Bill,

Thank you for your support.

The customer needs a very low leakage current.

Please share the application circuit.

sr.cho@arrow.com

Hello

See attached circuit that will switch in the Divider Network / FB pin using a P-Type MOSFET.  

NOTE -- Max voltage on the FB pin is 5.5V.  Will work for your application, but higher cell count will need a different gate drive.

BQ25173 FB pin MOSFET App ckt.pdf

Hi Bill,

FB pin leakage current : 0.7uA 

PG & STAT pin leakage current : 2.4uA

The customer's circuit has a PG & STAT pin pull-up connected to the OUT (VCAP).

The improvement circuit uses TPS7B8133 for STAT pull-up only.

Using OUT voltage (VCAP) for STAT pull-up seems to affect leakage current.

Should pull-up voltage use external voltage for low leakage current?