Texas Instruments BQ294504DRVR

Overview

BQ294504DRVR from Texas Instruments is a secondary overvoltage protection IC for 3-series Li-ion battery packs, featuring fixed 4.35 V OVP threshold, 6.5 s fault delay, ±10 mV detection accuracy, <1 µA supply current, and 6-pin WSON package. It independently monitors each cell voltage and drives an external N-channel FET to trigger fuse blow during overvoltage events in portable power tools and notebooks.

For engineers reviewing the BQ294504DRVR datasheet, BQ294504DRVR pinout, BQ294504DRVR application, or BQ294504DRVR equivalent, key selection criteria include OVP threshold tolerance, delay time consistency across temperature, leakage current per cell input (<100 nA), thermal pad grounding requirement, and compatibility with 2- or 3-cell stack configurations.

Technical Context

The BQ294504DRVR implements independent analog sensing of V1–VSS, V2–V1, and V3–V2 differential voltages using an internal multiplexer and precision comparator. Its fixed 4.35 V overvoltage threshold is factory-programmed with ±10 mV accuracy at 25°C and exhibits ≤54 mV drift over –40°C to +110°C.

Upon detection, a dedicated 6.5 s fixed-delay timer activates before asserting the open-drain OUT pin high to drive an external NMOS gate. The device resets only when all cell voltages fall below (VOV – VHYS), where hysteresis is 250–400 mV, ensuring stable recovery without oscillation.

Key Specifications

Pinout & Package

Package: 6-pin WSON (DRV), 2.00 mm × 2.00 mm body size, exposed thermal pad (PWRPAD) requiring PCB connection to VSS for proper thermal and electrical operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BQ294504DRVR, BQ294502DRVR offers identical accuracy and leakage but reduces fault confirmation time by 2.5 s, while BQ294524DRVR maintains the same delay but raises OVP to 4.45 V-enabling use with newer high-capacity cathode materials without changing layout or firmware.

Availability

BQ294504DRVR is available at Aetrix Electronics and suitable for power tools, notebook computers, and portable instrumentation requiring stable component supply with guaranteed long-term manufacturability and TI's production-data status.

Supply support for BQ294504DRVR 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 BQ2945xx family is designed specifically for secondary overvoltage protection in multi-cell Li-ion battery packs, emphasizing precision, ultra-low power, and robustness in harsh thermal environments.

FAQ

What is the overvoltage protection threshold and accuracy of the BQ294504DRVR?

The BQ294504DRVR has a factory-programmed overvoltage protection threshold of 4.35 V with ±10 mV accuracy at 25°C. Over the full operating temperature range (–40°C to +110°C), the total drift remains within ±54 mV, ensuring reliable secondary protection without calibration. This specification is verified per TI's production test flow and documented in Section 7.5 of the BQ294504DRVR datasheet.

How does the BQ294504DRVR interface with the external MOSFET and what is its output capability?

The BQ294504DRVR features an open-drain OUT pin that pulls high (to VDD level) during overvoltage events to drive the gate of an external N-channel MOSFET. It can sink ≥4.5 mA and exhibits <400 mV low-level voltage at 100 µA load, enabling direct interface with standard logic-level NMOS devices. The output remains asserted until all cell voltages drop below (4.35 V – VHYS), where hysteresis is 250–400 mV.

Does the BQ294504DRVR support both 2-cell and 3-cell Li-ion battery configurations?

Yes, the BQ294504DRVR supports both 2-series and 3-series Li-ion configurations. In a 2-cell setup, the V3 pin is shorted to V2; in a 3-cell stack, V1, V2, and V3 are connected to the respective cell positives. All three inputs are independently monitored, and OVP triggers if any single cell exceeds 4.35 V for the full 6.5 s delay period-ensuring comprehensive secondary protection regardless of stack count.

What is the purpose and activation method of Customer Test Mode (CTM) in the BQ294504DRVR?

Customer Test Mode (CTM) in the BQ294504DRVR reduces production test time for the 6.5 s delay timer by shortening it to >10 ms. CTM is activated by applying VDD at least 10 V higher than V3; it exits automatically when that differential drops. This mode is intended for final-pack functional testing and must avoid exceeding absolute maximum ratings on any pin, as specified in Section 8.4.3 of the BQ294504DRVR datasheet.

What are the critical PCB layout requirements for the BQ294504DRVR thermal pad (PWRPAD)?

The PWRPAD on the BQ294504DRVR must be soldered to the PCB's VSS copper plane with adequate thermal vias-TI specifies this connection as mandatory for correct operation and biasing. Layout guidelines require placing RC filters (RIN/CIN) as close as possible to V1/V2/V3 pins, routing VSS directly to the lowest cell's negative terminal, and ensuring the fuse-to-NFET trace can handle peak blow current. These requirements are detailed in Sections 11.1 and 9.2.1 of the BQ294504DRVR datasheet.