1 Features

? 1-A linear battery charger

– 3.0-V to 18-V input voltage operating range

– 25-V tolerant input voltage

– External resistor programmable operation:

? ILIM/VSET sets battery regulation voltage to

3.6V, 3.65 V, 4.02 V, 4.1V, 4.2 V, 4.35 V, or

4.4 V

? ILIM/VSET sets input current limit to 100

mA, 500 mA, or 1100 mA

? ISET to set charge current from 5 mA to 1 A

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

support

– 115-mΩ battery FET ON resistance

– Up to 3.125-A discharge current to support high

system loads

? Power path management for powering the system

and charging the battery

– Regulated system voltage (SYS) at 4.5 V

– Configurable input current limit

– USB Suspend mode supported

– Battery Tracking input voltage dynamic power

management (VINDPM) for high impedance

input sources

– Dynamic power path management optimizes

charging from weak adapters

? Ultra low quiescent current

– 4-μA in Battery Only mode

– 30-μA Input adapter Iq in sleep mode

– 3.2-μA Battery discharge current in Factory

Mode

? Integrated fault protection

– Input overvoltage protection (VIN_OVP)

– Battery undervoltage protection (BUVLO)

– 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)

– Safety timer fault

– ISET and ILIM/VSET pin short/open protection.

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 BQ25185 is a linear battery charger IC focusing

on small solution size and low quiescent current for

extending battery life. The device is available in a

leadless, small package with a thermal pad giving

thermal performance. The device can support up to

1-A charging and system loads of up to 3.125 A.