BQ25883: Battery not charging, REGN = 0V

Part Number: BQ25883

Tool/software:

We are using BQ25883 in our design for charging a 2S Li-ion battery (7.4V nominal).
The issue we are facing is that the battery is not charging. On checking, we observed that the REGN pin is at 0V.

Details:

  • Input power: VBUS = 5.0V

  • Battery voltage: 7.9V

  • I²C communication with the IC is working fine, and we are able to read/write registers.

  • However, charging does not start, and REGN remains at 0V.

Could you please help us debug this? Specifically, under what conditions will REGN not power up, and what checks should we perform to ensure proper IC operation?