Texas Instruments BQ294534DRVR

Overview

BQ294534DRVR from Texas Instruments is a secondary overvoltage protection IC for 3-series Li-ion battery packs, featuring a fixed 4.55 V OVP threshold, ±10 mV accuracy, 4 s fault detection delay, 1 µA supply current (VCELL < VPROTECT), and independent per-cell voltage monitoring. It drives an external N-channel FET to enable fuse blow during overvoltage events in portable power tools and notebooks.

For engineers reviewing the BQ294534DRVR datasheet, BQ294534DRVR pinout, BQ294534DRVR application, or BQ294534DRVR equivalent, key selection criteria include OVP threshold tolerance, delay timer stability across –40°C to +110°C, leakage current per cell input (<100 nA), thermal pad grounding requirement, and compatibility with 2- or 3-cell stack configurations.

Technical Context

The BQ294534DRVR implements independent analog sensing of three cell voltages (V1–VSS, V2–V1, V3–V2) via internal multiplexer, compares each against a factory-programmed 4.55 V threshold, and triggers a high-level OUT signal after a fixed 4 s delay if any cell exceeds the threshold. Hysteresis is fixed at 250–400 mV.

It operates in NORMAL mode when all cells remain below VOV, transitions to OVERVOLTAGE mode upon sustained overvoltage, and supports Customer Test Mode (CTM) with >10 ms reduced delay for production testing. The PWRPAD thermal pad must be electrically connected to VSS on PCB for functional reliability.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with BQ294532DRVR and BQ294522DRVR, the BQ294534DRVR provides the highest factory-set OVP threshold (4.55 V) in the family-enabling extended charge acceptance for newer high-capacity NMC cells while maintaining identical timing, leakage, and layout compatibility.

Availability

BQ294534DRVR is available at Aetrix Electronics and suitable for power tools, notebook computers, and portable medical instrumentation requiring stable component supply, long-term lifecycle support, and guaranteed traceability for safety-critical battery systems.

Supply support for BQ294534DRVR 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, with leadership in battery management and precision analog ICs.

The BQ2945xy product line delivers factory-programmed, low-power overvoltage protection ICs for 2- and 3-series Li-ion battery packs-designed specifically for secondary protection in space-constrained, thermally demanding portable equipment.

FAQ

What is the exact overvoltage protection threshold of the BQ294534DRVR?

The BQ294534DRVR has a factory-programmed overvoltage protection threshold of 4.55 V with ±10 mV accuracy at 25°C. This value is fixed and not adjustable. Temperature drift adds up to ±54 mV over –40°C to +110°C, and hysteresis is 250–400 mV to prevent chatter during recovery. The BQ294534DRVR specification is confirmed in TI's SLUSAJ3K datasheet Table 7-5.

Does the BQ294534DRVR support both 2-cell and 3-cell Li-ion battery configurations?

Yes, the BQ294534DRVR supports both configurations. For 3-cell stacks, V1, V2, and V3 are connected to each cell's positive terminals. For 2-cell stacks, V3 is shorted to V2 per TI's Figure 9-5. The BQ294534DRVR internally monitors (V1–VSS), (V2–V1), and (V3–V2) differentials and triggers if any exceeds 4.55 V.

How does the BQ294534DRVR drive the external MOSFET, and what are the output specifications?

The BQ294534DRVR drives the gate of an external N-channel FET via its OUT pin, which pulls high to ≥6 V (at VDD = 7.2 V, 100 µA load) when overvoltage is detected. It sinks ≤400 mV when low. Output rise time is 5 µs into 1 nF. The BQ294534DRVR datasheet specifies 4.5 mA short-circuit current capability, enabling robust FET turn-on even under worst-case conditions.

Is the thermal pad (PWRPAD) on the BQ294534DRVR optional or mandatory for operation?

The PWRPAD on the BQ294534DRVR is mandatory-not optional. TI's datasheet Section 6 and Figure 6-1 require electrical connection of PWRPAD to VSS on the PCB. Failure to do so risks incorrect biasing, thermal instability, and functional failure. The BQ294534DRVR's thermal resistance (RθJB = 110.7°C/W) assumes proper PWRPAD-to-plane soldering.

What is the supply current consumption of the BQ294534DRVR under normal operating conditions?

The BQ294534DRVR consumes ≈1 µA supply current (ICC) when all cell voltages remain below the 4.55 V protection threshold and VDD is between 3 V and 15 V. This ultra-low quiescent current is maintained across –40°C to +110°C, making the BQ294534DRVR ideal for long-shelf-life battery packs where self-discharge must be minimized.