Technical datasheet for the Texas Instruments bq27621-G1 single‑cell lithium‑ion battery fuel gauge.
The bq27621‑G1 is a system‑side battery fuel gauge that measures state‑of‑charge and remaining capacity for single‑cell Li‑ion batteries. It communicates via an I²C interface and includes an integrated LDO regulator, temperature sensor, and multiple power‑saving modes.
The device is offered in a 9‑pin YZF (1.62 mm × 1.58 mm) package suitable for space‑constrained applications such as smartphones, tablets, and portable media players. Detailed electrical specifications, pin functions, and command sets are provided for designers.
| Supply Current – NORMAL mode | 27 µA |
|---|---|
| Supply Current – SLEEP mode | 21 µA |
| Supply Current – HIBERNATE mode | 9 µA |
| LDO regulator output voltage | 1.8 V |
| VBAT pin input voltage range | -0.3 V to 6 V |
| VDD supply voltage range | -0.3 V to 2 V |
| Operating temperature range | -40 °C to 85 °C |
| Package type | 9‑pin YZF (1.62 mm × 1.58 mm) |
The 7‑bit device address is 1010101 (0x55).
It has 9 pins and is supplied in a YZF package measuring 1.62 mm × 1.58 mm.
The device supports NORMAL, SLEEP, HIBERNATE, and SHUTDOWN modes.
The ADC conversion time is 125 ms.