The is a specialized gas gauge and protection Integrated Circuit (IC) manufactured by Texas Instruments (TI). Unlike standard consumer-grade fuel gauges, the bq40370 is designed for impedance tracking and is frequently found in high-end battery packs, medical devices, and industrial tools where accuracy under load is non-negotiable.
Traditional fuel gauges use CEDV (Compensated End of Discharge Voltage) algorithms, which measure voltage and current but struggle with accuracy under dynamic loads. The bq40370 utilizes Generation 2 Impedance Track. This means it does not just measure voltage; it measures the internal impedance (resistance) of the battery cells in real-time. bq40370
This article provides a comprehensive breakdown of the bq40370, covering its architecture, key features, programming requirements, common failure modes, and how it compares to other TI gauges. To understand the bq40370, you must first understand TI’s proprietary Impedance Track™ technology. The is a specialized gas gauge and protection
| Feature | | BQ40Z50 | | :--- | :--- | :--- | | Algorithm | Impedance Track (Gen 2) | Impedance Track (Gen 5) | | Series Cells | 2 to 4 cells | 1 to 4 cells (with taps) | | Protection | Basic OV, UV, OT, Short | Enhanced (pre-charge, CTO, FET temp) | | Current Drive | Standard PFETs | High-side NFET drivers (more efficient) | | Legacy Support | Linux kernel support (old) | Requires new SMBus drivers | | Availability | NRND (Not Recommended for New Designs) | Active | The bq40370 utilizes Generation 2 Impedance Track
Introduction: What is the BQ40370? In the world of battery management systems (BMS), most enthusiasts and engineers are familiar with standard fuel gauges like the BQ20Z65, BQ30Z55, or the modern BQ40Z50 series. However, a specific part number often pops up in niche repair forums, datasheet deep-dives, and high-reliability application notes: bq40370 .