BQ24251RGER

BQ24251RGER is a Texas Instruments Li‑ion battery charger IC with integrated power-path management for single-cell cells. It charges a 1S Li‑ion/polymer battery from a 5V USB input (or other supply) while simultaneously powering the system, using CC/CV charging with automatic recharge.
Key features:
- Power-path management to power the system during charging
- Programmable charging current (set via external resistor ISET)
- CC/CV charging with precharge and termination
- Battery temperature monitoring input (NTC thermistor)
- Safety protections: over‑voltage, over‑current/short‑circuit, thermal shutdown
- Status outputs for charging/complete
- RoHS-compliant package in Tape & Reel (suffix RGER)
Applications include mobile devices, wearables, and USB-powered gadgets. For exact electrical specs, refer to the bq24251 datasheet.

BQ24251RGER features (concise):
- Single-cell Li-Ion battery charger with integrated power-path management.
- 5V USB input with system-load sharing (powers the system while charging).
- Charging algorithm: preconditioning, constant-current (CC), constant-voltage (CV) up to ~4.2V.
- End-of-charge termination with safety timer and automatic recharge.
- Battery temperature monitoring via NTC input for safety.
- Protections: overcurrent/short-circuit, overvoltage, thermal protection.
- Safe reverse current protection and fault detection.
- Status indicators/outputs for charging and fault (LED drive available).
- Small 8-pin RGER package (RoHS-compliant).

Pin count: 16 pins (WSON/VSSOP-16 style package).
Function: TI BQ24251RGER is a stand-alone Li‑ion battery charger with integrated power-path management. It accepts USB/DC input, charges a single-cell Li‑ion battery, and provides a SYS output to power the system while charging. It includes current regulation, safety protections (thermal, overvoltage/short-circuit), and status/configuration interfaces (I2C) for charging parameters.

- Manufacturer: Texas Instruments (TI).
- What kind of company: An American multinational semiconductor company that designs and manufactures analog, mixed-signal, and embedded processing integrated circuits, including battery-management and power-management devices like the bq series.

Typical applications for bq24251RGER:
- Portable devices with a single-cell Li‑ion/poly battery and USB input (charging + power-path management)
- Systems that need to charge the battery while powering the load
- Mobile electronics: smartphones, tablets, wearables, cameras, handheld gaming devices
- USB charging accessories: wall/auto chargers, docking stations, portable power banks
- Compact medical/industrial handheld equipment using one-cell packs
In short: efficient Li‑ion charging with protection for compact, USB-powered portable products.

WSON-8 (3x3 mm, leadless, RoHS) package.