BQ24251RGER - 2A I2C/Standalone Li-Ion Charger | Texas Instruments
MPN: BQ24251RGER β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.64 | $2.64 |
| 10 | $2.38 | $23.80 |
| 100 | $2.12 | $212.00 |
| 500 | $1.91 | $955.00 |
| 1,000 | $1.72 | $1,720.00 |
Drop-in alternatives for BQ24251RGER β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
BQ24250RGER
β Drop-Inπ Reference alternative (not in catalog)
BQ24251RGET
β Drop-Inπ Reference alternative (not in catalog)
BQ24250RGET
β Drop-Inπ Reference alternative (not in catalog)
BQ25601RTWR
β Drop-Inβ In Stock
$0.62 / Unit
View Datasheet βBQ24133RGYR
β Drop-Inβ In Stock
$3.1 / Unit
View Datasheet βMCP73871
β Drop-Inπ Reference alternative (not in catalog)
BQ24251RGER Maximum Ratings & Electrical Characteristics
| Charger Type | Switched-Mode (Buck) |
| Battery Chemistry | Lithium-Ion / Lithium-Polymer |
| Maximum Charge Current | 2 A |
| Input Voltage Range | 4.2 V to 10 V |
| Output Voltage Range | 3.5 V to 4.44 V |
| Input Current Limit Options | 100 mA, 500 mA, 900 mA, 1.5 A, 2 A |
| Interface | I2C (Host Mode) / Standalone |
| Power-Path Management | Yes (Separate Power Path) |
| USB Detection | BC1.2 Compatible D+/D- Detection |
| Operating Temperature Range | -40Β°C to +85Β°C |
| Package | VQFN-24 (4x4 mm) |
| Mounting Type | Surface Mount |
| Number of Pins | 24 |
| RoHS Status | Compliant |
| Watchdog Timer | Yes (I2C Host Mode) |
BQ24251RGER Pin Configuration
| Pin 1 | VBUS β Input supply from USB or adapter |
| Pin 2 | VBUS β Input supply from USB or adapter |
| Pin 3 | GND β Ground |
| Pin 4 | GND β Ground |
| Pin 5 | SDA β I2C data line |
| Pin 6 | SCL β I2C clock line |
| Pin 7 | INT β Interrupt output |
| Pin 8 | CE β Charge enable (active low) |
| Pin 9 | BAT β Battery connection |
| Pin 10 | BAT β Battery connection |
| Pin 11 | SYS β System output |
| Pin 12 | SYS β System output |
| Pin 13 | GND β Ground |
| Pin 14 | GND β Ground |
| Pin 15 | SW β Switching node |
| Pin 16 | SW β Switching node |
| Pin 17 | BOOT β Bootstrap capacitor connection |
| Pin 18 | PMID β Power middle point |
| Pin 19 | PMID β Power middle point |
| Pin 20 | D+ β USB D+ detection |
| Pin 21 | D- β USB D- detection |
| Pin 22 | TS β Temperature sense input |
| Pin 23 | ILIM β Input current limit set |
| Pin 24 | GND β Ground |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this digital IC. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
BQ24251RGER is suitable for 6 applications: Smartphones and Tablets, Portable Medical Devices, Portable Speakers and Audio Devices, Handheld GPS and Navigation Devices, Industrial Handheld Terminals, IoT Devices and Wearables.
Smartphones and Tablets
The BQ24251RGER is ideal for smartphones and tablets, providing up to 2A charge current and power-path management. Its I2C interface allows dynamic adjustment of charge parameters, while BC1.2 detection ensures safe USB charging. The separate power path enables instant-on operation even with a depleted battery, enhancing user experience. With a 4.2V to 10V input range, it supports both USB and AC adapters, making it a versatile solution for portable devices.
Recommended
Portable Medical Devices
In portable medical devices like glucose monitors and infusion pumps, reliable power management is critical. The BQ24251RGER's power-path management ensures the system operates continuously even when the battery is deeply discharged, which is essential for life-critical applications. Its thermal regulation and safety features protect the battery and system. The I2C interface allows precise control of charge current and voltage, meeting stringent medical requirements. The compact VQFN-24 package fits space-constrained designs.
Recommended
Portable Speakers and Audio Devices
The BQ24251RGER is well-suited for portable speakers and audio devices, where clean power and efficient charging are important. Its switched-mode charger achieves high efficiency, reducing heat generation in compact enclosures. The power-path management allows the device to play music while charging, without interrupting the audio. The selectable input current limit (100mA to 2A) ensures compatibility with various USB sources. The I2C interface enables host-controlled charging profiles for optimal battery health.
Recommended
Handheld GPS and Navigation Devices
Handheld GPS devices require reliable power management for extended outdoor use. The BQ24251RGER's power-path management enables instant-on operation from a deeply discharged battery, which is crucial when users need navigation immediately. Its wide input voltage range (4.2V to 10V) supports car adapters and USB chargers. The BC1.2 detection ensures safe charging from unknown USB ports. The device's low quiescent current helps extend battery life during standby, making it ideal for portable navigation.
Recommended
Industrial Handheld Terminals
Industrial handheld terminals, such as barcode scanners and PDAs, demand robust charging solutions. The BQ24251RGER operates over -40Β°C to +85Β°C, suitable for harsh environments. Its power-path management allows continuous operation during charging, minimizing downtime. The I2C interface enables remote monitoring and control of charging parameters, which is valuable in fleet management. The device's thermal regulation prevents overheating in sealed enclosures. With a 2A charge current, it reduces charging time, improving operational efficiency.
Recommended
IoT Devices and Wearables
For IoT devices and wearables, the BQ24251RGER offers a compact charging solution with power-path management. Its small VQFN-24 package and high efficiency make it suitable for space-constrained designs. The standalone mode allows simple operation without a host processor, reducing system complexity. The selectable input current limit (100mA) is ideal for energy-harvesting applications. The device's low leakage current helps preserve battery life in always-on IoT sensors. The I2C interface enables advanced battery diagnostics for predictive maintenance.
Recommended
Recommended Products Summary
Engineering reference data for BQ24251RGER β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | BQ24250RGER | BQ24251RGET | BQ25601RTWR | BQ24133RGYR | MCP73871 |
|---|---|---|---|---|---|---|
| Package | VQFN-24 (4x4 mm) | VQFN-24 (4x4 mm) | VQFN-24 (4x4 mm) | VQFN-24 (4x4 mm) | VQFN-24 (4x4 mm) | VQFN-24 (4x4 mm) |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Microchip Technology |
| Maximum Charge Current | 2 A | 2 A | 2 A | 3 A | 2 A | 1 A |
| Interface | I2C / Standalone | Standalone only | I2C / Standalone | I2C | I2C | Standalone |
| Power-Path Management | Yes | Yes | Yes | Yes | Yes | Yes |
| Input Voltage Range | 4.2 V to 10 V | 4.2 V to 10 V | 4.2 V to 10 V | 3.9 V to 14 V | 4.5 V to 17 V | 4.5 V to 7 V |
| USB BC1.2 Detection | Yes | Yes | Yes | Yes | No | No |
| Operating Temperature Range | -40Β°C to +85Β°C | -40Β°C to +85Β°C | -40Β°C to +85Β°C | -40Β°C to +85Β°C | -40Β°C to +85Β°C | -40Β°C to +85Β°C |
Key Differentiators
- I2C interface for dynamic control (vs BQ24250RGER)
- BC1.2 USB detection (vs BQ24133RGYR)
- Higher charge current than MCP73871 (vs MCP73871)
Design Notes
Place input and output capacitors close to the VBUS and SYS pins to minimize parasitic inductance. Use a 10uF ceramic capacitor on VBUS and a 10uF on SYS, with a 0.1uF high-frequency bypass. The SW node should have a short, wide trace to reduce EMI. Ensure a solid ground plane under the IC for thermal and electrical performance.
The BQ24251RGER can dissipate significant power during charging, especially at high input voltage and current. The VQFN-24 package has an exposed thermal pad that must be soldered to a copper pour for heat dissipation. For 2A charging, ensure at least 1 square inch of copper area on the PCB to keep junction temperature below 125Β°C.
In host mode, the watchdog timer must be serviced via I2C within the timeout period (typically 40 seconds) to avoid the charger reverting to standalone mode. Also, ensure the ILIM pin is properly set to match the adapter's current capability. Incorrect ILIM settings can cause input overcurrent and damage the adapter.
Compliance Information
RoHS compliant per TI product page. Not AEC-Q100 qualified. Halogen-free status not specified in provided data.
