TI BQ21040DBVT

The bq21040 device is a highly integrated lithium-ion and lithium-polymer linear battery charger designed for space-constrained portable applications. This device can be powered by a USB port or an AC adapter. The high input voltage range with input overvoltage protection supports low-cost, unregulated adapters. The bq21040 has a single power output that can charge the battery. If the average system load cannot fully charge the battery within the 10-hour safety timer period, the system load can be connected in parallel with the battery. Battery charging goes through the following three stages: regulation, constant current, and constant voltage. During all charging stages, the internal control loop monitors the IC junction temperature. When it exceeds the internal temperature threshold, it reduces the charging current. Both the charger power stage and the charging current sensing function are fully integrated. This charger features high-precision current and voltage regulation loop functions, charging status indication, and charging termination functions. The pre-charging current threshold and the termination current threshold are fixed at 20% and 10% respectively. The fast charging current value can be programmed via an external resistor.

• 1% charge voltage accuracy
• 10% charge current accuracy
• Low battery leakage current (1μA)
• Programmable charge current up to 800mA via external resistor
• 4.2V Li-Ion and Li-Polymer charger
• 30V rated input voltage; 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-circuit detection
• Overtemperature sense protection via NTC
• 10-hour fixed safety timer
• Status indication — Charge/Done
• Small SOT-23 package

• Electronic Point of Sale (EPOS)
• Medical Endoscopes
• BLE Speakers and Headphones
• Low-Power Handheld Devices