Texas Instruments BQ294708DSGR

Overview

BQ294708DSGR from Texas Instruments is a factory-programmed, 4-series Li-ion battery overvoltage protection IC with ±10 mV accuracy, 4.500 V OVP threshold, and external capacitor–programmed delay timer. It monitors each cell independently, delivers active-high CMOS output, and operates across –40°C to +110°C for notebook and UPS battery pack safety systems.

For engineers reviewing the BQ294708DSGR datasheet, BQ294708DSGR pinout, BQ294708DSGR application, or BQ294708DSGR equivalent, key selection criteria include per-cell voltage monitoring precision, CD-pin-based fault delay configurability, low 1 µA quiescent current, <100 nA input leakage, and WSON-8 (2 mm × 2 mm) thermal performance in high-reliability battery packs.

Technical Context

The BQ294708DSGR implements independent analog sensing of four stacked Li-ion cells (V1–VSS through V4–V3), comparing each against its fixed 4.500 V overvoltage threshold with 300 mV hysteresis. Its delay timer is fully controlled by an external capacitor on the CD pin, with built-in open/short detection ensuring fail-safe activation even if the capacitor fails.

In overvoltage mode, the device charges the CD capacitor, then discharges it at a fixed rate; OUT transitions high only after CD falls below a nominal threshold. The active-high CMOS output drives an NMOS FET to short the fuse to ground-enabling battery- or charger-powered fuse blow-without requiring external pull-up components.

Key Specifications

Pinout & Package

8-pin WSON (DSG) package with 2.00 mm × 2.00 mm footprint and exposed thermal pad connected to VSS per TI recommendation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BQ294704DSGR and BQ294713DSGR, the BQ294708DSGR provides the optimal 4.500 V threshold for standard 4S NMC Li-ion packs-balancing cycle life retention and capacity utilization while maintaining identical timing behavior, thermal performance, and PCB layout compatibility.

Availability

BQ294708DSGR is available at Aetrix Electronics and suitable for notebook battery packs, UPS backup systems, and industrial handheld devices requiring stable component supply, long-lifecycle support, and guaranteed traceable sourcing for safety-critical applications.

Supply support for BQ294708DSGR 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 delivering analog, embedded processing, and connectivity solutions with focus on reliability, precision, and energy efficiency.

The BQ2947 family is designed specifically for second-level overvoltage protection in multi-cell Li-ion battery packs-emphasizing hardware-enforced safety, minimal external components, and fail-safe diagnostics for consumer and industrial energy storage.

FAQ

What is the exact overvoltage protection threshold of the BQ294708DSGR?

The BQ294708DSGR has a factory-programmed overvoltage protection threshold of 4.500 V with ±10 mV accuracy at 25°C. This value is fixed and not adjustable; it applies to each monitored cell independently (V1–VSS, V2–V1, V3–V2, V4–V3). Temperature drift adds up to ±54 mV across –40°C to +110°C, as specified in the electrical characteristics table.

Does the BQ294708DSGR support 2-cell or 3-cell battery configurations?

Yes, the BQ294708DSGR supports 2-series and 3-series Li-ion configurations. For 2S operation, V3 and V4 pins must be shorted to V2; for 3S, V4 must be shorted to V3. All unused sense inputs retain full accuracy and leakage performance, and the internal monitoring logic automatically adapts-no configuration register or external jumper is needed.

How does the CD pin function in the BQ294708DSGR, and what capacitor value is recommended?

The CD pin connects to an external capacitor that sets the overvoltage delay time: t_CD = K × C_CD, where K = 10–20. With a 0.1 µF capacitor, delay ranges from 1–2 s. The BQ294708DSGR also detects CD pin faults-if the capacitor is open or shorted, the OUT pin activates immediately. TI recommends 0.1 µF X7R ceramic placed close to the pin per layout guidelines.

What is the output drive capability of the BQ294708DSGR's OUT pin?

The BQ294708DSGR features a CMOS active-high OUT pin capable of sourcing 4.5 mA when pulled low (I_OUTH) and sinking up to 14 mA when high (I_OUTL). Output voltage swings from VDD – 0.3 V (high) to ≤400 mV (low) at 100 µA load. It directly drives NMOS FET gates without buffering, enabling fast fuse-blow activation in battery protection circuits.

Is the BQ294708DSGR compatible with high-temperature battery environments?

Yes, the BQ294708DSGR is rated for operation from –40°C to +110°C ambient temperature, with full electrical specifications guaranteed across this range. Its WSON-8 package includes an exposed thermal pad tied to VSS, achieving 32.5°C/W junction-to-board thermal resistance-making it suitable for sealed battery packs in automotive-adjacent or industrial UPS enclosures.