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BQ27421YZFT-G1B

TIBQ27421YZFT-G1B

Texas Instruments
Battery Battery Monitor IC Lithium Ion 9-DSBGA
Active1,715 in stock
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Overview

The BQ27421YZFT-G1B is a system-side fuel gauge for single-cell Li-Ion batteries that utilizes Texas Instruments patented Impedance Track technology. It integrates a low-value 7 mOhm sense resistor and a dedicated LDO, allowing it to be powered directly from the battery while minimizing the external component count and board space.

Why Choose This Part

This gauge eliminates the need for complex battery modeling by automatically adjusting for aging, temperature, and self-discharge. Its integrated sense resistor reduces BOM complexity and layout challenges, while multiple low-power modes (down to 0.6 microamps in shutdown) help extend the shelf life of the end product.

Applications

Smartphones and Tablets
Provides accurate state-of-charge and state-of-health data for consumer mobile devices using internal sense resistors to save PCB space.
Wearable Devices
Utilizes the ultra-low 0.6 microamp shutdown current and small 9-DSBGA package for space-constrained, battery-powered electronics.
Portable Medical Instruments
Ensures reliable battery life monitoring and aging estimation for handheld diagnostic tools.
IoT Sensors
Monitors power levels in remote wireless nodes where low standby current is critical for long-term operation.

Key Specifications

Function Battery Monitor
Interface I2C
Mounting Type Surface Mount
Package / Case 9-UFBGA, DSBGA
Number of Cells 1
Battery Chemistry Lithium Ion
Operating Temperature -40degC ~ 85degC (TA)
Supplier Device Package 9-DSBGA

Getting Started

Communication is handled via a standard I2C interface, and the device can be configured by host software using TI provided drivers. For hardware evaluation, the BQ27421EVM-G1B evaluation module allows for rapid testing of the fuel gauging algorithm with specific battery chemistries.

Also Consider

BQ27441-G1 TITexas Instruments - Offers similar Impedance Track technology in a larger, easier-to-solder 12-pin SON package for prototyping.
MAX17048 Analog Devices - A simpler ModelGauge alternative that does not require a sense resistor, though it may offer less precision in dynamic load scenarios.
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