Texas Instruments BQ29419PWG4

Overview

BQ29419PWG4 from Texas Instruments is a secondary overvoltage protection IC for 2-, 3-, or 4-cell Li-ion battery packs, featuring fixed 4.30 V per-cell overvoltage threshold, <2 µA supply current, and programmable delay via external capacitor on CD pin. It monitors individual cell voltages (VC1–VC4), drives an external N-channel FET to blow a fuse upon overvoltage, and operates across –40°C to 110°C.

For engineers reviewing the BQ29419PWG4 datasheet, BQ29419PWG4 pinout, BQ29419PWG4 application, or BQ29419PWG4 equivalent, this page delivers verified technical context, validated pin functions, real-world use scenarios in portable instrumentation and notebook battery packs, and confirmed alternative parts with documented functional differences.

Technical Context

The BQ29419PWG4 implements precision voltage monitoring across up to four series-connected Li-ion cells using dedicated VC1–VC4 inputs, each compared against an internal reference. Its overvoltage detection accuracy is ±25 mV at 25°C and ±80 mV over full temperature range.

Upon detection of any cell exceeding 4.30 V, an internal 0.18 µA current source charges the external capacitor on CD; when CD reaches 1.2 V, OUT transitions high to trigger external fuse blow. Hysteresis is fixed at 250 mV to prevent oscillation during recovery.

Key Specifications

Pinout & Package

TSSOP-8 (PW) package, 3.0 mm × 4.4 mm body, 1.2 mm max height, 0.65 mm lead pitch, RoHS-compliant 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 BQ29412PWG4 and BQ29410PWG4, the BQ29419PWG4 provides the lowest overvoltage threshold (4.30 V) in the family, delivering maximum safety margin for conservative Li-ion cell management - critical in medical and industrial applications where overvoltage tolerance is strictly bounded.

Availability

BQ29419PWG4 is available at Aetrix Electronics and suitable for portable instrumentation, notebook computers, and medical portable devices requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for BQ29419PWG4 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 leadership in battery management solutions.

The bq2941x product line was designed specifically for secondary overvoltage protection in multi-cell Li-ion battery packs, providing hardware-enforced safety independent of host system firmware.

FAQ

What is the exact overvoltage protection threshold of the BQ29419PWG4?

The BQ29419PWG4 has a fixed overvoltage protection threshold of 4.30 V per cell, specified across the full operating temperature range (–40°C to 110°C). This value is factory-trimmed and does not require external programming. The BQ29419PWG4 datasheet confirms ±80 mV accuracy over temperature, making it suitable for safety-critical second-level protection where tight voltage margins are required.

How does the BQ29419PWG4 implement programmable delay time?

The BQ29419PWG4 uses an internal 0.18 µA current source to charge an external capacitor connected to the CD pin. When the CD voltage reaches 1.2 V, the OUT pin activates. Delay time is calculated as t_D = (1.2 V × C_DELAY) / 0.18 µA - for example, a 0.22 µF capacitor yields ~1.5 seconds. The BQ29419PWG4 automatically discharges CD if overvoltage clears before threshold is reached.

Can the BQ29419PWG4 monitor fewer than four cells?

Yes, the BQ29419PWG4 supports 2-, 3-, or 4-cell configurations. For 2-cell use, connect VC1 = VC2 = VC3 = VDD and VC4 to the bottom cell terminal; for 3-cell, tie VC1 = VC2 = VDD and route VC3/VC4 accordingly. The BQ29419PWG4 datasheet provides explicit connection diagrams and sequencing rules to prevent false triggering in reduced-cell setups.

What package type and footprint does the BQ29419PWG4 use?

The BQ29419PWG4 uses the TSSOP-8 (PW) package: 3.0 mm × 4.4 mm body, 1.2 mm max height, 0.65 mm lead pitch. It is RoHS-compliant with NiPdAu lead finish and MSL Level-2 rating (260°C, 1 year). The BQ29419PWG4 shares pinout and footprint with other bq2941x variants in PW packaging, enabling layout reuse across voltage-threshold options.

Does the BQ29419PWG4 require external components beyond the CD capacitor?

Yes - in addition to the CD timing capacitor, the BQ29419PWG4 requires external RC filters on VC1–VC4 inputs (R_IN = 100 Ω–1 kΩ, C_IN = 0.01–0.1 µF) and on VDD (R_VD ≤ 1 kΩ, C_VD ≥ 0.1 µF) to suppress noise and ensure stable operation during pulse charging. These values are specified in the BQ29419PWG4 recommended operating conditions table and are mandatory for reliable overvoltage detection.