Texas Instruments BQ29415PWR

Overview

BQ29415PWR from Texas Instruments is a secondary overvoltage protection IC for 2-, 3-, or 4-cell Li-ion battery packs, featuring fixed 4.60 V per-cell overvoltage threshold, <2 µA supply current, and programmable delay via external capacitor on CD pin. It drives an external N-channel FET to blow a fuse during overvoltage events and supports stable operation during pulse charging in notebook computers and portable instrumentation.

For engineers reviewing the BQ29415PWR datasheet, BQ29415PWR pinout, BQ29415PWR application, or BQ29415PWR equivalent, key selection criteria include cell count support (2–4 series), precision overvoltage detection accuracy (±80 mV over –40°C to 110°C), low ICC (<2 µA), CD-pin-based delay timing, and TSSOP-8 package compatibility with industrial temperature range (–40°C to 110°C).

Technical Context

The BQ29415PWR implements independent voltage monitoring across up to four cell sense inputs (VC1–VC4) referenced to GND, with internal comparator circuitry that triggers only when any single cell exceeds 4.60 V. Its protection sequence initiates a controlled charge of an external capacitor at the CD pin using a 0.18 µA current source.

Upon CD pin voltage reaching 1.2 V, the open-drain OUT pin transitions high to activate an external NCH FET; recovery occurs only after all cells fall below (4.60 V – Vhys), where hysteresis is 320 mV. The device maintains immunity to supply ripple and remains stable during pulse-charge conditions without false triggering.

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 BQ29415PWR, BQ29419PWR provides earlier overvoltage cutoff for conservative chemistries, while BQ29412PWR offers intermediate protection for standard LiCoO₂ cells-both share identical timing, power, and thermal specs but differ solely in factory-set threshold voltage.

Availability

BQ29415PWR is available at Aetrix Electronics and suitable for notebook computers, portable medical devices, and industrial handheld scanners requiring stable component supply with guaranteed long-term manufacturability and consistent parametric performance.

Supply support for BQ29415PWR 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 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 secondary overvoltage protection in multi-cell Li-ion battery packs, delivering factory-trimmed accuracy, ultra-low power, and robust operation in portable and industrial applications.

FAQ

What is the exact overvoltage protection threshold voltage of the BQ29415PWR?

The BQ29415PWR has a fixed, factory-trimmed overvoltage protection threshold of 4.60 V per cell, specified with ±80 mV accuracy over the full operating temperature range of –40°C to 110°C. This value is unique to the BQ29415PWR within the bq2941x family and cannot be adjusted externally. The BQ29415PWR uses this precise threshold to enforce second-level hardware protection in 2-, 3-, or 4-cell Li-ion battery configurations.

Does the BQ29415PWR require external resistors or voltage dividers to set its overvoltage threshold?

No, the BQ29415PWR does not require external resistors or voltage dividers. Its 4.60 V overvoltage threshold is internally trimmed and fixed at wafer test, eliminating component count and drift-related inaccuracies. All voltage sensing is performed directly on the VC pins, with each pin rated for up to 28 V absolute maximum. The BQ29415PWR achieves this precision without user calibration or external feedback networks.

How is the overvoltage detection delay time programmed on the BQ29415PWR?

The BQ29415PWR uses an external capacitor connected to the CD pin to program the overvoltage detection delay. A 0.18 µA internal current source charges the capacitor; when CD voltage reaches 1.2 V, the OUT pin activates. For example, a 0.22 µF capacitor yields a typical delay of 1.5 seconds. The BQ29415PWR's delay calculation follows td = (1.2 V × CDELAY) / 0.18 µA, enabling precise, passive timing control without microcontroller involvement.

Can the BQ29415PWR be used in both 2-cell and 4-cell Li-ion battery configurations?

Yes, the BQ29415PWR supports 2-, 3-, and 4-cell Li-ion configurations through flexible VC pin wiring. In 2-cell mode, VC1 and VC2 connect to the top of the stack, VC3 is left unconnected, and VC4 connects to the bottom cell's positive terminal. TI provides validated connection sequences in the datasheet to prevent false triggering. The BQ29415PWR maintains full accuracy and timing integrity across all supported configurations without reconfiguration.

What package type and environmental rating does the BQ29415PWR use?

The BQ29415PWR is supplied in a TSSOP-8 (PW) package: 3.0 mm × 4.4 mm body, 1.2 mm max height, 0.65 mm lead pitch, NiPdAu lead finish, and MSL Level-2-260°C-1 year rating. It operates across –40°C to 110°C ambient temperature and meets RoHS requirements. The BQ29415PWR's PW package is optimized for automated assembly and thermal performance in space-constrained battery pack modules.