Texas Instruments bq21040 Li-Ion & Li-Pol Battery Charger

Texas Instruments bq21040 Li-Ion and Li-Pol Battery Charger is a highly integrated linear battery charger targeted at space-limited portable applications. The charger device operates from either a USB port or AC adapter. The high input voltage range with input overvoltage protection supports low-cost unregulated adapters. The Texas Instruments bq21040 has a single power output that charges the battery. A system load can be placed in parallel with the battery as long as the average system load does not keep the battery from charging fully during the 10-hour safety timer. The battery is charged in three phases: conditioning, constant current, and constant voltage. An internal control loop monitors the IC junction temperature and reduces the charge current if an internal temperature threshold is exceeded in all charge phases.

Features

  • Charging
    • 1% charge voltage accuracy
    • 10% charge current accuracy
    • Low battery leakage current (1µA)
    • Programmable charge current using external resistor up to 800mA
    • 4.2V Li-Ion and Li-Pol charger
  • Protection
    • 30V input rating; with 6.6V input overvoltage protection
    • Input voltage dynamic power management
    • 125°C thermal regulation; 150°C thermal shutdown protection
    • OUT short-circuit protection and ISET short detection
    • Overtemperature sensing protection through NTC
    • Fixed 10-hour safety timer
  • System
    • Status indication – charging/done
  • Available in a small SOT-23 package

Applications

  • EPOS
  • Medical endoscopes
  • BLE speaker and headsets
  • Low-power handheld devices

Simplified Schematic

Schematic - Texas Instruments bq21040 Li-Ion & Li-Pol Battery Charger
Publicado: 2016-09-09 | Actualizado: 2022-03-11