Texas Instruments BQ296223DSGT

Overview

BQ296223DSGT 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, active-high fault output (OUT), and 3.3 V regulated supply (REG) delivering up to 2 mA. It is used in notebook PC battery protection circuits to prevent cell overcharge and power always-on RTCs.

For engineers reviewing the BQ296223DSGT datasheet, BQ296223DSGT pinout, BQ296223DSGT application, or BQ296223DSGT equivalent, key selection considerations include its 8-pin WSON (2 mm × 2 mm) package, 2.5 µA typical quiescent current with REG disabled, 100 nA max per-cell input leakage, self-disable behavior below undervoltage threshold (2.5 V), and compatibility with NMOS FET-based fuse control architectures.

Technical Context

The BQ296223DSGT implements independent per-cell voltage monitoring across up to four series-connected Li-ion cells using precision analog comparators referenced to a factory-trimmed 4.50 V overvoltage threshold. An internal fixed 6.5 s delay timer initiates upon any cell exceeding VOV and drives the CMOS-active-high OUT pin to trigger external FET-based fuse blow circuitry.

Its integrated 3.3 V regulated supply (REG) delivers up to 2 mA with ±30 mV load regulation (0–2 mA), self-disables when any cell falls below 2.5 V (with 300 mV hysteresis and 6 s delay), and requires a 0.47 µF ceramic capacitor at the REG pin for stability. Input leakage remains below 100 nA per sense pin (V1–V4), enabling high-impedance stack monitoring without significant parasitic discharge.

Key Specifications

Pinout & Package

8-pin WSON package (2.00 mm × 2.00 mm) with exposed thermal pad connected to VSS. Pin 1 is top-left corner (marking dot adjacent), pin numbering follows standard counter-clockwise sequence.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BQ296223DSGT, BQ296221DSGT offers identical timing and regulation but a 5 mV higher OVP threshold, while BQ296231DSGT raises OVP by 100 mV-both require revalidation of charge termination algorithms and thermal safety margins.

Availability

BQ296223DSGT is available at Aetrix Electronics and suitable for notebook PC battery packs, ultrabook energy management systems, and medical portable device power modules requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for BQ296223DSGT 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 experience in battery safety ICs and high-reliability power solutions.

The BQ296xxx family is designed specifically for secondary overvoltage protection in multi-cell Li-ion battery packs, integrating precision voltage monitoring, programmable delay timers, and regulated auxiliary supplies to simplify pack-level safety architecture.

FAQ

What is the factory-programmed overvoltage threshold for BQ296223DSGT?

The BQ296223DSGT has a factory-programmed overvoltage 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 (±54 mV at 110°C) and supports reliable second-level protection in 2-, 3-, or 4-series Li-ion configurations. BQ296223DSGT uses this fixed setting to eliminate calibration overhead in high-volume battery pack production.

How does the regulated output (REG) of BQ296223DSGT behave during battery discharge?

The REG pin of BQ296223DSGT delivers a stable 3.3 V output up to 2 mA, but automatically disables when any monitored cell voltage falls below the factory-set 2.5 V undervoltage threshold for 6 seconds. Once all cells rise above 2.8 V (2.5 V + 300 mV hysteresis), REG re-enables. This self-disable function prevents excessive battery drain and protects downstream circuits like RTCs from brownout conditions. BQ296223DSGT implements this behavior without external control signals.

What is the purpose of the OUT pin on BQ296223DSGT and how is it driven?

The OUT pin on BQ296223DSGT is a CMOS active-high fault signal output that transitions to logic high after a fixed 6.5 s delay when any cell exceeds 4.50 V. It sources up to 4.5 mA and is designed to directly drive the gate of an NMOS FET, which shorts the fuse to ground to initiate battery isolation. Unlike open-drain alternatives, BQ296223DSGT's active-high OUT simplifies external driver design and eliminates need for pull-up resistors in most implementations.

Can BQ296223DSGT be used in a 2-series battery configuration?

Yes, BQ296223DSGT supports 2-, 3-, and 4-series Li-ion configurations. In a 2-series setup, only V1 and V2 pins are used for sensing; V3 and V4 are shorted to V2 and V1 respectively per TI layout guidelines. The device automatically ignores unused inputs and maintains full OVP/UV functionality across the active cells. BQ296223DSGT's architecture ensures identical accuracy and timing performance regardless of stack size, making it scalable across product families.

What external components are mandatory for stable operation of BQ296223DSGT?

Mandatory external components for BQ296223DSGT include: (1) 0.47 µF ceramic capacitor between REG and VSS (placed within 2 mm), (2) 1 kΩ resistor + 0.1 µF capacitor on each Vx sense line (V1–V4) for noise filtering, and (3) 0.1 µF capacitor from VDD to VSS. A 5 Ω series resistor on the REG line is recommended if VSS cannot be connected first during assembly. These values ensure measurement accuracy, REG stability, and ESD robustness as specified in the BQ296223DSGT datasheet.