Texas Instruments BQ2944L0DRBR

Overview

BQ2944L0DRBR from Texas Instruments is a second-level overvoltage protection IC for 2-, 3-, or 4-series Li-ion battery packs, featuring latch-enabled OUT output, 4.35 V fixed overvoltage threshold (±25 mV accuracy at 0°C–60°C), <2 µA typical supply current, and external capacitor-controlled delay timing. It operates across –40°C to +110°C and is used in notebook computers and power tools for cell-level voltage fault containment.

For engineers reviewing the BQ2944L0DRBR datasheet, BQ2944L0DRBR pinout, BQ2944L0DRBR application, or BQ2944L0DRBR equivalent, key selection considerations include latch behavior, 4.35 V OVP precision, QFN-8 (DRB) package thermal performance, and compatibility with 2–4 series cell topologies requiring secondary protection before pack-level cutoff.

Technical Context

The BQ2944L0DRBR implements independent per-cell voltage monitoring using precision comparators referenced to an internal bandgap, detecting overvoltage on any VCx input (VC1–VC2, VC2–VC3, VC3–VC4, or VC4–GND). When triggered, it sources 140 nA into the CD pin to charge an external capacitor until reaching 1.2 V, after which the OUT pin latches high.

Latching is persistent until CD is shorted to GND; no automatic reset occurs upon voltage normalization. The device supports Customer Test Mode (CTM), reducing delay scale factor from 9.0 s/µF to 0.08 s/µF for accelerated production testing-though CTM alters OVP accuracy and is not for functional operation.

Key Specifications

Pinout & Package

Package: 8-pin SON (DRB), 3.0 mm × 3.0 mm, 0.5 mm pitch, 1.0 mm max height, exposed thermal pad requiring PCB soldering for thermal and mechanical integrity.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BQ2944L0DRBR, BQ29440DRBR offers automatic reset but lacks fail-safe hold, while BQ2944L9DRBR provides identical latch behavior at a lower OVP threshold-requiring revalidation of delay timing and system-level fault thresholds.

Availability

BQ2944L0DRBR is available at Aetrix Electronics and suitable for notebook computers, power tools, and portable medical devices requiring stable component supply with guaranteed long-term sourcing for industrial battery programs.

Supply support for BQ2944L0DRBR 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 specializing in analog, embedded processing, and power management technologies, with decades of leadership in battery management solutions.

The BQ2944L0DRBR belongs to TI's bq2944x family of secondary protection ICs, designed specifically for robust, low-power, hardware-based overvoltage containment in multi-cell Li-ion battery packs.

FAQ

What is the overvoltage protection threshold of the BQ2944L0DRBR?

The BQ2944L0DRBR has a fixed overvoltage protection (OVP) threshold of 4.35 V, with ±25 mV accuracy over 0°C to 60°C. This value is factory-trimmed and applies to any individual cell voltage monitored across VC1–VC2, VC2–VC3, VC3–VC4, or VC4–GND. The BQ2944L0DRBR does not support user-adjustable thresholds.

How does the latch function work on the BQ2944L0DRBR OUT pin?

The BQ2944L0DRBR OUT pin transitions high after the programmed delay and remains latched high indefinitely-even if cell voltages return to safe levels. To reset the latch, the CD pin must be shorted to GND, discharging the external capacitor. This behavior ensures fail-safe shutdown until deliberate operator or system intervention.

What package type and thermal characteristics does the BQ2944L0DRBR use?

The BQ2944L0DRBR uses an 8-pin SON (DRB) package measuring 3.0 mm × 3.0 mm with 0.5 mm pitch and an exposed thermal pad. Its junction-to-board thermal resistance (qJB) is 19.3°C/W, and junction-to-ambient (qJA) is 50.5°C/W on a JEDEC-standard high-K board-enabling reliable operation up to +110°C ambient.

Can the BQ2944L0DRBR be used in 2-series, 3-series, and 4-series Li-ion configurations?

Yes, the BQ2944L0DRBR supports all three configurations: 2S (using VC1, VC2, GND), 3S (VC1, VC2, VC3, GND), and 4S (VC1, VC2, VC3, VC4, GND). Pin assignment remains identical; unused VCx pins must be left unconnected-not tied to GND or VDD-to prevent erroneous triggering.

What is the purpose of Customer Test Mode (CTM) in the BQ2944L0DRBR?

Customer Test Mode (CTM) reduces the overvoltage delay scale factor from 9.0 s/µF to 0.08 s/µF by raising VDD ~9.5 V above VC1, enabling rapid production-line verification of OVP functionality. CTM is not for normal operation-it slightly degrades OVP accuracy and must be exited by power-cycling the BQ2944L0DRBR.