Texas Instruments BQ29414PWRG4

Overview

BQ29414PWRG4 from Texas Instruments is a 4-cell secondary overvoltage protection IC for Li-ion battery packs, featuring fixed 4.55 V per-cell overvoltage threshold, programmable delay via external capacitor on CD pin, and ultra-low 2 µA supply current. It operates across –40°C to 110°C and drives an external N-channel FET to blow a fuse during overvoltage events in notebook battery management systems.

For engineers reviewing the BQ29414PWRG4 datasheet, BQ29414PWRG4 pinout, BQ29414PWRG4 application, or BQ29414PWRG4 equivalent, key selection criteria include cell-count flexibility (2–4 cells), high-accuracy voltage detection (±50 mV at 25°C), ripple rejection under pulse charging, and compatibility with TSSOP-8 PCB layouts requiring no redesign for legacy bq2941x family integration.

Technical Context

The BQ29414PWRG4 implements independent per-cell voltage monitoring using precision internal references and comparator circuitry. Each VC pin (VC1–VC4) senses individual cell voltages in series-connected Li-ion stacks, with differential input tolerance up to ±8 V between adjacent sense terminals.

Upon detecting any cell exceeding 4.55 V, it initiates a controlled delay by charging an external capacitor via a 0.18 µA current source on the CD pin; when CD reaches 1.2 V, the open-drain OUT pin pulls high to trigger external protection circuitry. Recovery occurs only after all cells fall below 4.55 V minus 320 mV hysteresis.

Key Specifications

Pinout & Package

TSSOP-8 (PW) package: 3.0 mm × 4.4 mm, 1.2 mm max height, lead pitch 0.65 mm, RoHS-compliant CU-NiPdAu finish, MSL Level-2 (260°C, 1 year).

Key Features

Applications

Equivalent & Alternatives

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

Compared with BQ29414PWRG4, BQ29413PWR offers a 50 mV lower trip point for conservative protection, while BQ29415PWR provides 50 mV headroom for higher-voltage chemistries-both retain identical delay programming, temperature range, and PCB layout compatibility.

Availability

BQ29414PWRG4 is available at Aetrix Electronics and suitable for notebook computer battery packs, portable instrumentation power systems, and industrial portable equipment requiring stable component supply and long-lifecycle support for legacy designs.

Supply support for BQ29414PWRG4 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 innovation in battery safety and precision analog ICs.

The bq2941x product line was designed specifically for redundant, hardware-based overvoltage protection in multi-cell Li-ion battery packs-targeting applications where firmware-independent safety is mandatory.

FAQ

What is the exact overvoltage protection threshold of the BQ29414PWRG4?

The BQ29414PWRG4 has a fixed overvoltage protection threshold of 4.55 V per cell, specified with ±50 mV accuracy at 25°C and ±80 mV over the full –40°C to 110°C operating range. This value is laser-trimmed at wafer test and does not require external calibration. The BQ29414PWRG4 maintains this threshold stability across supply voltage (4–25 V) and load conditions, making it suitable for safety-critical second-level protection in certified battery packs.

Can the BQ29414PWRG4 be used in 2-cell or 3-cell battery configurations?

Yes, the BQ29414PWRG4 supports 2-, 3-, or 4-cell Li-ion configurations. For 2-cell use, connect VC1 = VC2 = VC3 = VDD and VC4 to the bottom cell's positive terminal; for 3-cell, tie VC1 = VC2 = VDD and route VC3–VC4–GND. All configurations retain the 4.55 V per-cell threshold and full delay timing functionality. The BQ29414PWRG4's input structure tolerates differential voltages up to ±8 V between adjacent VC pins, ensuring robust operation regardless of cell count.

How is the overvoltage delay time set on the BQ29414PWRG4?

The BQ29414PWRG4 uses an internal 0.18 µA current source to charge an external capacitor connected to the CD pin; delay time t_D = (1.2 V × C_DELAY) / 0.18 µA. With a 0.22 µF capacitor, typical delay is 1.5 seconds. The BQ29414PWRG4 automatically discharges the CD capacitor via an internal switch if overvoltage clears before 1.2 V is reached, preserving full delay for subsequent events. No external resistors or clocks are needed.

Is the BQ29414PWRG4 pin-compatible with other bq2941x variants?

Yes, the BQ29414PWRG4 shares identical TSSOP-8 pinout and electrical behavior with all bq2941x family members (bq29410–bq29419), including matching VC1–VC4, GND, CD, VDD, and OUT assignments. The only functional difference is the overvoltage threshold (4.55 V), so PCBs designed for bq29413PWR or bq29415PWR can accept BQ29414PWRG4 without layout changes-enabling drop-in qualification for different voltage grades.

What is the recommended decoupling for the VDD pin of the BQ29414PWRG4?

Texas Instruments recommends a 0.1 µF ceramic capacitor placed within 2 mm of the VDD pin to ground, with short, wide traces to minimize inductance. The BQ29414PWRG4 draws <2 µA quiescent current but requires stable supply during overvoltage detection transients. Additional bulk capacitance (e.g., 4.7 µF tantalum) may be added upstream if VDD is shared with noisy circuits. The BQ29414PWRG4 datasheet specifies CVD = 0.1 µF minimum for supply filtering.