Texas Instruments BQ294624DRVT

Overview

BQ294624DRVT from Texas Instruments is a single-cell lithium-ion battery secondary overvoltage protector IC with fixed 4.45V OVP threshold and 6.5s fault detection delay. It monitors cell voltage via V1 input, drives an external N-channel FET through its open-drain OUT pin to trigger fuse blow in overvoltage events, and operates across –40°C to +110°C ambient temperature. It is used in tablet and portable instrumentation battery packs requiring precise, low-power secondary protection.

For engineers reviewing the BQ294624DRVT datasheet, BQ294624DRVT pinout, BQ294624DRVT application, or BQ294624DRVT equivalent, key selection criteria include its ±10mV OVP accuracy at 25°C, 1µA supply current under undervoltage conditions, dual VSS ground pins for robust PCB layout, 6-pin WSON (DRV) package with thermal pad, and fixed 6.5s delay timing without external components.

Technical Context

The BQ294624DRVT implements a dedicated analog comparator-based overvoltage detection circuit that compares V1 against a factory-trimmed 4.45V reference. Upon threshold exceedance, a fixed internal timer initiates a 6.5s delay before asserting the OUT pin high to activate an external NMOS FET.

It features two electrically isolated VSS pins tied internally to IC ground and the battery's negative terminal, enabling low-impedance return paths and improved noise immunity. The device enters Customer Test Mode (CTM) when VDD exceeds V1 by ≥10V, reducing delay to ~15ms for production testing without altering functional behavior.

Key Specifications

Pinout & Package

Package: 6-pin WSON (DRV), 2.00mm × 2.00mm body, 0.8mm max height, exposed thermal pad (PWRPAD) connected to VSS.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BQ294624DRVT, BQ294604DRVT offers identical timing but lower OVP voltage for conservative protection, while BQ294682DRVT trades accuracy and threshold for faster 4s response-both require no PCB changes but differ in trip point and delay calibration.

Availability

BQ294624DRVT is available at Aetrix Electronics and suitable for tablet battery packs, portable instrumentation, slates, and medical monitors requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for BQ294624DRVT 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 company specializing in analog and embedded processing technologies, with leadership in power management, signal chain, and battery management solutions.

The BQ2946xx family is designed specifically for secondary-level overvoltage protection in single-cell Li-ion battery packs, delivering factory-trimmed accuracy, ultra-low power, and robust thermal performance in space-constrained portable devices.

FAQ

What is the overvoltage protection threshold and accuracy of the BQ294624DRVT?

The BQ294624DRVT has a fixed factory-programmed overvoltage protection (OVP) threshold of 4.45V with an accuracy of ±10mV at 25°C. This value remains stable across temperature, with drift bounded between –54mV and +54mV from –40°C to +110°C. The BQ294624DRVT uses this precise threshold to initiate a 6.5s delay before asserting its OUT pin, ensuring reliable secondary protection without external calibration components.

How does the BQ294624DRVT interface with external circuitry for fuse control?

The BQ294624DRVT drives an external N-channel MOSFET via its open-drain OUT pin. When overvoltage is detected and the 6.5s delay expires, OUT transitions high (to VDD level), turning on the FET to short the fuse to ground. The BQ294624DRVT specifies an output sink capability of ≥100µA at ≤400mV, ensuring robust gate drive under worst-case temperature and voltage conditions.

What are the recommended operating conditions for the BQ294624DRVT?

The BQ294624DRVT operates with VDD between 3V and 8V, V1 input between 0V and 5V, and ambient temperature from –40°C to +110°C. Its supply current is ≤2µA across this full range, and V1 input leakage remains below 100nA. These conditions ensure reliable secondary protection in demanding portable and industrial battery applications using the BQ294624DRVT.

Does the BQ294624DRVT require external passive components for basic operation?

Yes-the BQ294624DRVT requires external RC filters: a 1kΩ resistor (RIN) and 0.1µF capacitor (CIN) on the V1 sense line, and a 1kΩ resistor (RVD) and 0.1µF capacitor (CVD) on the VDD supply line. These components suppress noise and ensure stable overvoltage detection. Layout guidelines specify placing them adjacent to the BQ294624DRVT pins to minimize loop area and EMI susceptibility.

What is the purpose of the dual VSS pins on the BQ294624DRVT?

The BQ294624DRVT features two VSS pins (pins 3 and 4) that must both be connected externally to the battery's negative terminal (CELL–). This dual-ground configuration reduces impedance in the return path, improves noise rejection during overvoltage transients, and supports proper thermal pad (PWRPAD) connection-ensuring stable operation and accurate voltage sensing in high-density battery pack layouts using the BQ294624DRVT.