Texas Instruments BQ294704DSGR

Overview

BQ294704DSGR from Texas Instruments is a precision overvoltage protection IC for 2- to 4-series Li-ion battery packs, featuring factory-programmed 4.400 V OVP threshold, ±10 mV accuracy at 25°C, external capacitor-programmed delay (1–2 s with 0.1 µF), and CMOS active-high output drive. It operates across –40°C to +85°C and supports notebook and UPS battery backup systems.

For engineers reviewing the BQ294704DSGR datasheet, BQ294704DSGR pinout, BQ294704DSGR application, or BQ294704DSGR equivalent, key selection factors include its 4.400 V fixed OVP threshold, 8-pin WSON package, low 1 µA quiescent current, independent cell monitoring capability, and integrated CD-pin timeout detection for open/shorted capacitor fault coverage.

Technical Context

The BQ294704DSGR implements independent analog voltage comparators per cell input (V1–VSS through V4–V3) to detect overvoltage conditions against its fixed 4.400 V threshold. Its delay timer uses an external capacitor on the CD pin, with internal charge/discharge circuitry that triggers OUT after 1–2 s and includes dedicated timeout detection for CD pin faults.

It operates in two functional modes: Normal Mode (all cells below 4.400 V, OUT inactive low) and Overvoltage Mode (any cell ≥4.400 V, OUT transitions high after delay). The device supports customer test mode via CD-to-VSS shorting, reducing delay to ≤170 ms for production-line verification.

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 BQ294705DSGR and BQ294703DSGR, the BQ294704DSGR offers the industry-standard 4.400 V OVP point for modern high-energy-density NMC and NCA cells, delivering optimal safety margin above 4.2 V nominal while avoiding premature cutoff during transient charge peaks.

Availability

BQ294704DSGR is available at Aetrix Electronics and suitable for notebook battery management, UPS backup systems, and portable test equipment requiring stable component supply, long-lifecycle support, and guaranteed traceability.

Supply support for BQ294704DSGR 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.

The BQ2947 family was designed specifically for second-level hardware overvoltage protection in multi-cell Li-ion battery packs, targeting applications demanding autonomous, analog-based fault response independent of system microcontrollers.

FAQ

What is the exact overvoltage protection threshold of the BQ294704DSGR?

The BQ294704DSGR has a factory-programmed overvoltage protection threshold of 4.400 V, with ±10 mV accuracy at 25°C and ±54 mV maximum drift across the full –40°C to +110°C operating range. This value is laser-trimmed during manufacturing and cannot be adjusted externally. The BQ294704DSGR's fixed 4.400 V threshold is documented in TI's SLUSB15K datasheet Table 4 and Section 6.5 Electrical Characteristics.

Does the BQ294704DSGR support 2-cell and 3-cell battery configurations?

Yes, the BQ294704DSGR supports 2-, 3-, and 4-series Li-ion configurations. For 2S operation, V3 and V4 pins are shorted together; for 3S, only V4 is shorted to V3. TI's datasheet Figure 8-2 and Figure 8-3 provide validated schematic connections. All unused sense inputs must be tied to the adjacent higher-potential node to maintain proper bias and avoid floating inputs.

How does the CD pin fault detection work on the BQ294704DSGR?

The BQ294704DSGR continuously monitors the CD pin for valid charge/discharge behavior. If the external capacitor is open-circuited (no voltage rise) or shorted to VSS (no discharge phase), the internal timeout circuit detects the anomaly within milliseconds and forces the OUT pin active - ensuring fail-safe response even with defective timing components. This behavior is detailed in Section 7.3.1.4 of the SLUSB15K datasheet.

What is the purpose of the customer test mode on the BQ294704DSGR?

The customer test mode on the BQ294704DSGR reduces overvoltage response time from 1–2 s to ≤170 ms by shorting the CD pin to VSS. This allows rapid functional verification during production testing without requiring precise capacitor placement or long wait times. The mode is explicitly defined in Section 7.4.3 and Figure 7-3 of the official datasheet.

Can the BQ294704DSGR be used with an open-drain output configuration?

No - the BQ294704DSGR is exclusively configured as CMOS Active High. Open-drain Active Low variants exist in the BQ2947 family (e.g., BQ294707), but the "04" suffix denotes the 4.400 V / Active High version. Attempting to use BQ294704DSGR as open-drain will result in incorrect logic levels and potential system malfunction. Always verify suffix coding against TI's Device Comparison Table.