Texas Instruments BQ294707DSGR

Overview

BQ294707DSGR from Texas Instruments is a dedicated 2- to 4-series Li-ion battery overvoltage protection IC with factory-programmed 4.225 V OVP threshold, ±10 mV accuracy, and N-channel open-drain active-low output. It monitors each cell independently, uses an external capacitor on the CD pin to set a 1–2 s fault delay, and delivers <100 nA per-cell input leakage for ultra-low-power battery pack supervision in portable power systems.

For engineers reviewing the BQ294707DSGR datasheet, BQ294707DSGR pinout, BQ294707DSGR application, or BQ294707DSGR equivalent, this device serves as a second-level safety monitor requiring precise cell voltage sensing, configurable fault timing, low-quiescent current operation, and robust open-drain output drive for fuse control in high-reliability battery packs.

Technical Context

The BQ294707DSGR implements independent analog voltage comparators per cell input (V1–VSS through V4–V3), with a fixed 4.225 V overvoltage detection threshold and only 50 mV hysteresis-significantly lower than other variants in the family. Its NCH open-drain OUT pin requires an external pull-up resistor and sinks up to 14 mA when active, enabling direct drive of NMOS FETs for fuse-blowing circuits.

Overvoltage response is governed by an external RC timer on the CD pin: a 0.1 µF capacitor yields 1–2 s nominal delay, while shorting CD to VSS activates Customer Test Mode with ≤170 ms response. The device also includes CD pin timeout detection to force fault output if the capacitor is open or shorted during overvoltage events.

Key Specifications

Pinout & Package

Package: 8-pin WSON (DSG), 2.00 mm × 2.00 mm, exposed thermal pad (PowerPAD™) recommended to be connected to VSS.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BQ294707DSGR, BQ294701DSGR offers higher OVP threshold and active-high output but lacks fail-safe CD fault detection, while BQ294715DSGR provides matching 50 mV hysteresis and precision but requires external inversion to drive NMOS fuses-making BQ294707DSGR optimal for direct, robust, low-leakage open-drain implementation.

Availability

BQ294707DSGR is available at Aetrix Electronics and suitable for notebook battery packs, industrial UPS systems, portable medical devices, and test equipment requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for BQ294707DSGR 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 delivering analog and embedded processing solutions for industrial, automotive, and personal electronics markets.

The BQ2947 family is designed specifically for secondary overvoltage protection in multi-cell Li-ion battery packs, emphasizing precision, ultra-low power, and fail-safe fault response in safety-critical energy storage systems.

FAQ

What is the exact overvoltage protection threshold for BQ294707DSGR?

The BQ294707DSGR has a factory-programmed overvoltage protection threshold of 4.225 V with ±10 mV accuracy at 25°C. This value is fixed and not adjustable; it applies to each monitored cell (V1–VSS, V2–V1, V3–V2, V4–V3) and remains stable across –40°C to +110°C with specified drift limits.

How does the CD pin function in BQ294707DSGR, and what capacitor value is recommended?

The CD pin in BQ294707DSGR connects to an external capacitor that sets the overvoltage delay timer. With a 0.1 µF capacitor, the delay is 1–2 seconds. The pin also includes open/short fault detection: if the capacitor is missing or shorted to ground, the OUT pin activates immediately-ensuring fail-safe behavior. TI specifies K = 10–20 in t_CD = K × C_CD.

What output configuration does BQ294707DSGR use, and how should it be interfaced?

BQ294707DSGR uses an N-channel open-drain active-low output (OUT pin). It must be externally pulled up to a logic-compatible voltage (e.g., VDD or system rail) via a resistor. When active, it sinks up to 14 mA-sufficient to directly drive the gate of an NMOS FET used in fuse-blowing circuits without additional buffering.

Can BQ294707DSGR be used in 2-series or 3-series Li-ion configurations?

Yes, BQ294707DSGR supports 2S, 3S, and 4S Li-ion configurations. For 2S operation, V3 and V4 pins must be shorted to V2; for 3S, V4 must be shorted to V3. These connections are explicitly defined in TI's application schematics (Figures 8-2 and 8-3) and maintain correct internal voltage referencing and fault detection integrity.

What is the supply current and input leakage specification for BQ294707DSGR?

BQ294707DSGR draws ≈1 µA supply current (I_DD) when all cell voltages are below the OVP threshold. Input leakage at each Vx pin (V1–VSS through V4–V3) is guaranteed <100 nA at 25°C-critical for minimizing inter-cell imbalance and preserving long-term battery health in high-impedance sensing networks.