2A charge current for single-cell Li-Ion/Polymer packs
The BQ24109RHLR is a constant-current, constant-voltage charger IC from the bqSWITCHER™ series, designed for single-cell Lithium Ion or Lithium Polymer battery packs. It delivers a programmable charge current up to 2A, with a termination voltage of 4.2V — the standard float voltage for these chemistries. The input supply can range up to 16V, making it compatible with common 5V USB adapters or 12V wall warts without an external pre-regulator.
Industrial temperature range and fault protection
On-chip fault protection covers over-temperature and over-voltage conditions — the charger shuts down before the battery or the IC itself is stressed beyond safe limits.
Package and programming options
Housed in a 20-VFQFN with exposed pad (3.5x4.5 mm body), the part requires a thermal land pattern on the PCB to pull heat from the die. The charge current and safety timer are programmable via external resistors — no I²C or SMBus interface needed, which simplifies the BOM for a standalone charger block.