Texas Instruments BQ771801DPJT

Overview

BQ771801DPJT from Texas Instruments is a dedicated overvoltage protection IC for 2- to 5-series Li-ion battery packs, featuring ±10 mV OVP accuracy, 3 s internal delay timer, and N-channel open-drain active-low output. It monitors each cell independently and is used in cordless power tools and e-bike battery management systems.

For engineers reviewing the BQ771801DPJT datasheet, BQ771801DPJT pinout, BQ771801DPJT application, or BQ771801DPJT equivalent, key selection criteria include its 4.275 V fixed overvoltage threshold, 0.05 V hysteresis, 1 µA quiescent current, and QFN-8 (3.0 mm × 4.0 mm) package compatibility with high-density PCB layouts.

Technical Context

The BQ771801DPJT implements independent per-cell voltage sensing using five differential inputs (V1–V5 relative to VSS), comparing each against a precision 4.275 V reference. Its internal delay timer initiates upon first OVP detection and expires after 3 s to assert the active-low OUT signal.

This device operates across –40°C to 110°C with supply voltage from 3 V to 25 V, supports Customer Test Mode (CTM) for accelerated production-line validation with ~15 ms fault detection, and requires external RC filters on all sense inputs for noise immunity.

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 BQ771803DPJT and BQ771802DPJT, the BQ771801DPJT offers the optimal balance of response time (3 s delay) and threshold (4.275 V) for mainstream 18650/21700-based power tool and e-mobility packs, avoiding premature shutdown while ensuring robust safety margin.

Availability

BQ771801DPJT is available at Aetrix Electronics and suitable for handheld power tools, cordless vacuum cleaners, and light electric vehicle battery packs requiring stable component supply and long-lifecycle support.

Supply support for BQ771801DPJT 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 delivering analog and embedded processing solutions for industrial, automotive, and personal electronics markets.

The BQ7718 family is designed specifically for standalone overvoltage protection in multi-cell Li-ion battery packs, emphasizing precision, low power, and functional safety readiness without requiring microcontroller supervision.

FAQ

What is the overvoltage protection threshold of the BQ771801DPJT?

The BQ771801DPJT has a fixed overvoltage protection threshold of 4.275 V with ±10 mV accuracy at 25°C. This value remains stable across temperature, with worst-case drift of ±54 mV at 110°C. The BQ771801DPJT uses an internal precision reference to eliminate external component variation, making it ideal for high-reliability battery packs where consistent cell-level cutoff is mandatory.

How does the BQ771801DPJT handle multiple series cell configurations?

The BQ771801DPJT supports 2-, 3-, 4-, and 5-series Li-ion configurations via five independent sense inputs (V1–V5). Unused inputs (e.g., V4 and V5 in a 2S pack) are left floating with no impact on accuracy or functionality. Each input draws <100 nA, minimizing imbalance effects. The BQ771801DPJT monitors all connected cells simultaneously and triggers fault if any exceeds 4.275 V.

What is the purpose of Customer Test Mode (CTM) in the BQ771801DPJT?

Customer Test Mode (CTM) reduces the BQ771801DPJT's overvoltage delay from 3 s to approximately 15 ms by applying VDD ≥10 V above V5. This enables rapid functional verification during battery pack manufacturing without altering hardware. CTM exits automatically when the VDD-to-V5 differential drops below 10 V. The BQ771801DPJT maintains full electrical specifications in CTM, supporting high-throughput production testing.

Does the BQ771801DPJT require external components for basic operation?

Yes - the BQ771801DPJT requires external RC filters on all sense inputs (RIN = 1 kΩ, CIN = 0.1 µF typical) and on VDD (RVD, CVD) for noise immunity and stability. An external pull-up resistor on OUT is mandatory for its NCH open-drain active-low output. These components are specified in TI's BQ771801DPJT datasheet Section 9.1 and must be placed close to respective pins per layout guidelines.

Is the BQ771801DPJT compatible with functional safety standards?

Yes - the BQ771801DPJT is Functional Safety-Capable, with documentation available to support ISO 26262 ASIL-B or IEC 61508 SIL-2 system-level safety analysis. It features high-accuracy OVP (±10 mV), predictable 3 s delay timing, and robust ESD ratings (±2000 V HBM). While the BQ771801DPJT itself is not certified, its architecture and failure modes are documented to aid safety-certified BMS design.