1 Features

• 1A linear battery charger

– 3.0V to 5.5V input voltage operating range for

battery-to-battery charging and USB adapters

– Configurable battery regulation voltage with

0.5% accuracy from 3.6V to 4.65V in 10mV

steps

– Li-ion, Li-Poly, and LiFePO4 chemistries

support

– 5mA to 1A configurable fast charge current

– 55mΩ battery FET ON resistance

– Up to 3A discharge current to support high

system loads

– Configurable NTC charging profile thresholds

including JEITA support

• Power path management for powering the system

and charging the battery

– Regulated system voltage (SYS) ranging from

4.4V to 4.9V addition to battery voltage tracking

and input pass-though options

– Battery Tracking input voltage dynamic power

management (VINDPM) for high impedance

input sources

• Ultra low quiescent current

– 4μA in Battery Only mode

– 30μA Input adapter Iq in sleep mode

• One push-button wake-up and reset input

• Integrated fault protection

– Input overvoltage protection (VIN_OVP)

– Battery short protection (BATSC)

– Battery overcurrent protection (BATOCP)

– Input current limit protection (ILIM)

– Thermal regulation (TREG) and thermal

shutdown (TSHUT)

– Battery thermal fault protection (TS)

– Watchdog and safety timer fault

2 Applications

• TWS headset and charging case

• Smart glasses, AR and VR

• Smart watches and other wearable devices

• Retail automation and payment

• Building automation

3 Description

The BQ21088 is a linear battery charger IC focusing

on small solution size and low quiescent current for

extending battery life. The device is available in an

8-ball chipscale package which does not need HDI

PCB process for fabrication thereby reducing the PCB

cost. The device can support up to 1A charging and

system loads of up to 3A.