BQ25150: Selecting part for solar charger

Csaba Toth

Part Number: BQ25150
Other Parts Discussed in Thread: BQ25601, TPS561201

Hi,

I am looking for i2c solar battery charger for IoT device.

Actually the BQ25150 or BQ25061 what fit to my ideas. As I see those two parts are very identical in battery charging algorithm.

The solar panel is 6V what usually can go up to 7.3V when no load.

The input is 20V tolerant, but what happens at 7.3V input when the data sheet specify typical 3.4 - 5.5 V input voltage?

There are new battery-supercapacitor parts on the market for 3.8V, 4.2V applications.

Do you think the devices are appropriate to charge those caps?

Thanks, Csaba

0 Raheem over 5 years ago

Hello,

I'll suggest using the BQ25601 which has as adjustable OVP. The OVP on BQ25150 is 5.5V which cannot be changed.

0 Csaba Toth over 5 years ago in reply to Raheem

Hi Raheem,

Thanks for suggesting, but Bq25601 is not suitable for my purpose because the minimum charge voltage is 3.85V not suitable for LiFePO4 charging.

What is the real effect in case of BQ25150/BQ25062 the input voltage over 5.5V?

It shuts down? Or efficiency degraded?

Csaba

0 Raheem over 5 years ago in reply to Csaba Toth

The input FET turns off when VIN is above 5.5V. The device was designed to be used with USB as input which is why the OVP is around 5.5V

0 Csaba Toth over 5 years ago in reply to Raheem

What buck converter would you recommend to step down the solar voltage to 5V?

0 Raheem over 5 years ago in reply to Csaba Toth

Hello,

Take a look at the TPS561201

Power management forum