Texas Instruments BQ771818DPJR

Overview

BQ771818DPJR from Texas Instruments is a dedicated overvoltage protection IC for 2- to 5-series Li-ion battery packs, featuring ±10 mV OVP accuracy, 4.300 V fixed overvoltage threshold, and 1 s internal delay timer. It operates across –40°C to 110°C with ultra-low 1 µA supply current and <100 nA per-cell input leakage, deployed in cordless power tools and e-bike battery management systems.

For engineers reviewing the BQ771818DPJR datasheet, BQ771818DPJR pinout, BQ771818DPJR application, or BQ771818DPJR equivalent, key selection criteria include its CMOS active-high output drive, QFN-8 (3.00 mm × 4.00 mm) package, functional safety documentation support, and compatibility with 2–5 cell stack topologies requiring precise, low-power cell voltage monitoring.

Technical Context

The BQ771818DPJR independently monitors up to five differential cell voltages (V1–VSS through V5–V4) using precision internal references. Its overvoltage detection logic triggers a fixed 1 s delay timer upon any cell exceeding 4.300 V, after which the CMOS-active-high OUT pin drives high to signal fault.

It supports Customer Test Mode (CTM) with sub-15 ms fault detection latency for production-line validation. The device requires external RC filters on all Vx inputs and VDD, and integrates no internal regulator - VDD accepts 3 V to 25 V unregulated supply directly from the pack.

Key Specifications

Pinout & Package

Package: 8-pin WSON (DPJ), 3.00 mm × 4.00 mm, wettable flank, RoHS-compliant, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BQ771800DPJR, BQ771818DPJR offers identical electrical behavior and pinout but reflects updated TI manufacturing revision and orderable status; versus MP26123, it delivers integrated 2–5 cell monitoring, factory-trimmed timing, and functional safety support - eliminating external components and certification effort.

Availability

BQ771818DPJR is available at Aetrix Electronics and suitable for handheld power tools, e-bike battery packs, and UPS backup systems requiring stable component supply, long-lifecycle assurance, and automotive-grade temperature performance.

Supply support for BQ771818DPJR 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 over 50 years of leadership in battery management innovation.

The BQ7718 family was designed specifically for standalone, high-accuracy overvoltage protection in multi-cell Li-ion battery packs - prioritizing ultra-low power, factory-trimmed timing, and functional safety readiness over programmability or communication interfaces.

FAQ

What is the overvoltage protection threshold and accuracy of the BQ771818DPJR?

The BQ771818DPJR has a fixed overvoltage protection threshold of 4.300 V with ±10 mV accuracy at 25°C and ±54 mV maximum drift over –40°C to 110°C. This specification ensures reliable cell-level shutdown before lithium plating occurs, and is verified per TI's DC Characteristics table in the official datasheet. The BQ771818DPJR achieves this using laser-trimmed internal references and matched input circuitry.

Does the BQ771818DPJR support 2-cell, 3-cell, and 5-cell battery configurations?

Yes, the BQ771818DPJR supports 2-series to 5-series Li-ion battery stacks via its five differential sense inputs (V1–VSS through V5–V4). Unused inputs (e.g., V4 and V5 in a 3-cell pack) are left floating per TI's application guidance. The BQ771818DPJR does not require configuration pins or firmware - topology support is inherent to its analog sensing architecture.

What is the purpose of Customer Test Mode (CTM) in the BQ771818DPJR?

Customer Test Mode (CTM) in the BQ771818DPJR reduces the overvoltage delay timer from 1 s to less than 15 ms, enabling rapid functional verification during battery pack manufacturing. CTM is activated by applying VDD ≥10 V higher than V5; the BQ771818DPJR automatically exits CTM when the differential drops below threshold. This feature cuts final-test cycle time without compromising field reliability.

What package type and footprint does the BQ771818DPJR use?

The BQ771818DPJR uses an 8-pin WSON package (designation DPJ), measuring 3.00 mm × 4.00 mm with wettable flanks for automated optical inspection. It is identical in footprint and solder profile to other BQ7718x DPJR variants, enabling drop-in replacement across the family. The BQ771818DPJR is not offered in MSOP; DGK-package variants carry different part numbers (e.g., BQ771818DGKR).

How does the BQ771818DPJR handle overvoltage hysteresis and recovery?

The BQ771818DPJR implements 0.300 V nominal hysteresis (range 0.25–0.40 V) between overvoltage trip and release points. After triggering, the OUT pin remains active until all cell voltages fall below (4.300 V – VHYS), preventing chatter during marginal recovery. This hysteresis is internal and unadjustable - a key differentiator from comparator-based solutions requiring external resistors. The BQ771818DPJR guarantees this behavior across its full temperature range.