1 Features

? Input voltage up to 30 V tolerant

? Input Voltage Based Dynamic Power Management

(VINDPM) tracking battery voltage

? Automatic Sleep Mode for low power consumption

– 350-nA battery leakage current

– 80-μA input leakage current when charge

disabled

? Supports 1-cell Li-Ion, Li-Poly, and LiFePO4

? External resistor programmable operation

– VSET to set battery regulation voltage:

? Li-Ion: 4.05 V, 4.15 V, 4.2 V, 4.35 V, 4.4 V

? LiFePO4: 3.5 V, 3.6 V, 3.7 V

– ISET to set charge current from 10 mA to 800

mA

? High accuracy

– ±0.5 charge voltage accuracy

– ±10 charge current accuracy

? Charging features

– Precharge current 20 of ISET

– Termination current 10 of ISET

– Battery tracking input voltage dynamic power

management (VINDPM) for solar charging

– BIAS pin for charging function control

– Open-drain output for status and fault indication

– Open-drain output for power good indication

? Integrated fault protection

– 18.1-V IN overvoltage protection

– VSET based OUT overvoltage protection

– 1000-mA overcurrent protection

– 125°C thermal regulation; 150°C thermal

shutdown protection

– OUT short-circuit protection

– VSET, ISET pins short/open protection

2 Applications

? Smart trackers

? Low-power handheld devices

? Auxilliary solar chargers

3 Description

The BQ25176M is an integrated 800-mA linear solar

charger for 1-cell Li-Ion, Li-Polymer, and LiFePO4

batteries with continual charge mode and battery

tracking VINDPM. The device has a single power

output that charges the battery. When the system

load is placed in parallel with the battery, the charge

current is shared between the system and the battery.

The device has four phases for charging a Li-Ion/

Li-Poly battery: trickle charge to bring the battery

voltage up to VBAT_SHORT, precharge to recover a fully

discharged battery, fast-charge constant current to

supply the bulk of the charge, and voltage regulation

to reach full capacity.

In all charge phases, an internal control loop monitors

the IC junction temperature and reduces the charge

current if an internal temperature threshold, TREG, is

exceeded.

The charger power stage and charge current sense

functions are fully integrated. The charger function

has high accuracy current and voltage regulation

loops, charge status display, and automatic charge

termination. The charge voltage and fast charge

current are programmable through external resistors.

The precharge and termination current threshold track

the fast charge current setting.