BQ27520YZFT-G4

The bq27520YZFT-G4 is Texas Instruments’ single‑cell Li‑ion/polymer fuel gauge IC. It provides real‑time state of charge (SOC) and remaining capacity estimates by combining coulomb counting with adaptive impedance‑tracking (for improved SOC accuracy), plus monitoring of voltage, current, and temperature. The device stores calibration data (design capacity, Qmax, full/empty thresholds) in nonvolatile memory and reports SOC, voltage, current, temperature, and estimated time to empty via an I2C/SMBus‑compatible interface. It supports automatic learning, data memory for user/app data, and built‑in protection/flag outputs. The gauge typically requires only a sense resistor and a few passive components, making integration straightforward for portable devices. Developers use TI’s bqStudio tools to configure and program the device. The “G4” suffix denotes a specific package/variant option. Overall, the bq27520YZFT-G4 simplifies battery management by delivering accurate gauging with minimal external components.

Direct drop-in equivalents do not exist. BQ27520YZFT-G4 is TI’s single‑cell Impedance Track fuel gauge. Closest TI substitutes are other BQ2752x devices (e.g., BQ27500, BQ27510) with similar SMBus interfaces but different capacity ranges. For cross‑vendor options, consider Maxim MAX17330/MAX17331 or other Li‑ion fuel gauges, and verify interface, programming data, and features.

Here are the key features of the bq27520YZFT-G4:
- Single-cell Li‑ion/Li‑polymer fuel gauge using TI’s Impedance Track technology for accurate SoC/SoH estimation.
- Coulomb counting with automatic learning of true design/full-charge capacity; tracks aging and adjusts estimates.
- Monitors and reports: voltage, current, temperature, and impedance (for health estimation).
- Outputs state information: State of Charge (SoC), State of Health (SoH), Design Capacity, Full Charge Capacity, Remaining Capacity, and Time to Empty.
- Programmable thresholds and alerts for over/under voltage, over/under temperature, and overcurrent (interrupt pin available).
- I2C/SMBus compatible digital interface for data access and control (host communications).
- Low power operation with standby/sleep modes suitable for portable devices.
- On-chip data flash for calibration and user configuration of capacity and alert thresholds.
- Minimal external parts (requires a sense resistor for coulomb counting and basic passive support).
- Robust, suitable for embedded battery packs in consumer electronics.

- Pin count: 8 pins (in its package for BQ27520YZFT-G4).
- Function: Battery fuel gauge (gas gauge) with Impedance Track. Monitors Li‑ion cell voltage, current, temperature and impedance; provides state of charge, remaining capacity, and other battery data to a host MCU over I2C/SMBus.

- Manufacturer: Texas Instruments (TI).
- What kind of company: American multinational semiconductor company that designs and manufactures analog and embedded processing ICs; one of the world’s largest semiconductor makers.

BQ27520YZFT-G4 applications:
- Single-cell Li‑ion/Li‑polymer battery-powered devices
- Consumer portable electronics (smartphones, tablets, wearables, cameras, handheld gaming)
- IoT devices and wireless sensors
- Medical devices using a 1S battery
- Any embedded system needing accurate state-of-charge (SoC), state-of-health (SoH), and impedance-tracking via I2C
Notes: it’s a 1S fuel gauge with Impedance Track, suitable for compact, battery-powered products requiring precise runtime estimates.

VQFN-16 package (3.0 × 3.0 mm) with an exposed pad; lead-free/RoHS-compliant.