Texas Instruments BQ296222DSGT

Overview

BQ296222DSGT from Texas Instruments is a high-accuracy, low-power overvoltage protector IC for 2–4 series Li-ion battery packs, featuring factory-programmed 4.50 V OVP threshold, 6.5 s fixed delay timer, ±10 mV OVP accuracy, 3.0 V regulated output (2 mA max), and 8-pin WSON (2 mm × 2 mm) package. It monitors each cell independently and drives external FETs to blow fuses during overvoltage faults in notebook PC battery protection circuits.

For engineers reviewing the BQ296222DSGT datasheet, BQ296222DSGT pinout, BQ296222DSGT application, or BQ296222DSGT equivalent, key selection criteria include its 4.50 V ±10 mV OVP setting, 3.0 V/2 mA regulated supply with self-disable on cell undervoltage, active-high OUT signal, 1.2 µA quiescent current with REG disabled, and compatibility with 2–4 cell stacks requiring precise secondary protection and RTC power delivery.

Technical Context

The BQ296222DSGT implements independent per-cell voltage monitoring using precision analog comparators referenced to a factory-trimmed bandgap, triggering a fixed 6.5 s internal delay timer upon detection of any cell exceeding 4.50 V. Its architecture includes a dedicated regulated LDO output stage with built-in short-circuit current limiting (4 mA) and thermal foldback, plus self-disable logic that disables REG when any cell falls below the factory-set 3.0 V UV threshold for 6 s.

It operates across –40°C to +110°C ambient temperature, supports up to 30 V absolute maximum VDD–VSS, and delivers CMOS-compatible active-high fault signaling via the OUT pin capable of sourcing 4.5 mA. Input leakage at all Vx pins remains below 100 nA, enabling high-impedance cell sensing without significant stack imbalance.

Key Specifications

Pinout & Package

8-pin WSON package (2.00 mm × 2.00 mm, 0.5 mm pitch) with exposed thermal pad connected to VSS. Pin 1 marked by dot; top view orientation matches Figure 5-2 in SLUSBU5V.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar overvoltage protection applications.

Compared with BQ296222DSGT, BQ296221DSGT offers higher OVP (4.55 V) and 3.3 V REG but requires redesign of downstream 3.0 V circuitry, while BQ296230DSGT lowers OVP to 4.35 V with identical 3.0 V UV and REG - making it the closest functional alternative for conservative voltage margins without changing power rail requirements.

Availability

BQ296222DSGT is available at Aetrix Electronics and suitable for notebook PC battery management, ultrabook safety systems, and medical portable device packs requiring stable component supply, long-lifecycle support, and guaranteed traceable sourcing.

Supply support for BQ296222DSGT includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and power management technologies, with decades of expertise in battery safety ICs and high-reliability power solutions.

The BQ296xxx product line is designed specifically for secondary overvoltage protection and regulated auxiliary supply in multi-cell Li-ion battery packs, targeting applications where hardware-enforced safety and ultra-low quiescent current are mandatory.

FAQ

What is the factory-programmed overvoltage protection threshold for BQ296222DSGT?

The BQ296222DSGT has a factory-programmed overvoltage protection (OVP) threshold of 4.50 V with ±10 mV accuracy at 25°C. This value is laser-trimmed during manufacturing and cannot be adjusted externally. The threshold remains stable across temperature, with drift bounded to ±54 mV at 110°C, ensuring reliable secondary protection in demanding thermal environments.

Does BQ296222DSGT support 2-cell, 3-cell, and 4-cell Li-ion battery configurations?

Yes, BQ296222DSGT supports 2-series, 3-series, and 4-series Li-ion battery stacks. It monitors differential voltages across V1–VSS, V2–V1, V3–V2, and V4–V3. For 2S designs, V3 and V4 are shorted to V2; for 3S, V4 is shorted to V3. All configurations use the same 4.50 V OVP threshold and 6.5 s delay timer, with no external configuration required.

What is the function of the REG pin on BQ296222DSGT and what load can it drive?

The REG pin on BQ296222DSGT delivers a factory-programmed 3.0 V regulated output capable of supplying up to 2 mA. It powers always-on circuits such as real-time clocks or supervisor ICs. The output includes short-circuit current limiting (4 mA) and automatically disables when any monitored cell voltage falls below 3.0 V for 6 seconds, preventing excessive discharge.

How does the OUT pin behave during an overvoltage event on BQ296222DSGT?

During an overvoltage event, the OUT pin on BQ296222DSGT transitions from low to active-high after a fixed 6.5 s internal delay. It sources up to 4.5 mA and is designed to drive the gate of an external NMOS FET, creating a low-impedance path from fuse to ground. This allows battery or charger current to blow the fuse and disconnect the pack - a hardware-fail-safe action independent of firmware.

What is the recommended PCB layout practice for the VSS connection on BQ296222DSGT?

Texas Instruments mandates that the VSS pin of BQ296222DSGT be connected to system ground *before* any other pin during cell attachment or PCB testing. Failure to do so risks damaging the REG pin due to uncontrolled capacitor discharge. If VSS-first connection cannot be guaranteed, a 5 Ω resistor must be placed in series with the REG capacitor to limit inrush current and protect the IC during assembly.