Texas Instruments BQ34Z100PWR

Overview

BQ34Z100PWR from Texas Instruments is a standalone wide-range fuel gauge IC for Li-ion and LiFePO₄ battery packs (3 V–65 V), implementing Impedance Track™ algorithm to deliver <1% state-of-charge accuracy across temperature (–40°C to 85°C) and aging conditions, supporting >65 Ah capacity and >32 A charge/discharge currents in portable power tools and UPS systems.

For engineers reviewing the BQ34Z100PWR datasheet, BQ34Z100PWR pinout, BQ34Z100PWR application, or BQ34Z100PWR equivalent, key selection considerations include dual-interface support (I²C/HDQ), integrated coulomb counter with ±10 µV offset, low-power operation (<19 µA in FULL SLEEP), NTC thermistor interface, and SHA-1/HMAC authentication for secure battery pack identification.

Technical Context

The BQ34Z100PWR operates autonomously using an internal 8.389 MHz high-frequency oscillator and 32.768 kHz low-frequency oscillator to time coulomb integration and temperature sampling. Its 14-bit integrating ADC measures voltage across SRP/SRN sense resistors with ±0.034% FSR INL and 1 s conversion time, while a separate 14-bit ADC monitors TS and BAT inputs with 8 MΩ input impedance and 125 ms conversion latency.

Impedance Track™ modeling runs continuously in NORMAL mode, leveraging OCV-voltage correlation, aging compensation, and self-discharge estimation. Communication occurs via I²C (400 kHz, open-drain SDA/SCL) or HDQ (single-wire, 190–250 µs cycle time), with automatic mode transitions between NORMAL (<140 µA), SLEEP (<64 µA), and FULL SLEEP (<19 µA) based on host activity and timeout events.

Key Specifications

Pinout & Package

Package: 14-pin TSSOP (5.00 mm × 4.40 mm), RoHS-compliant, surface-mountable with standard reflow profile.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar fuel gauge applications.

Compared with BQ40Z50-R1 and MAX17055, the BQ34Z100PWR uniquely balances wide-input voltage support (3–65 V), Impedance Track™ accuracy, SHA-1 security, and dual I²C/HDQ connectivity in a compact 14-pin TSSOP-making it the preferred choice for industrial and medical battery packs where gauging fidelity, longevity, and authentication are non-negotiable.

Availability

BQ34Z100PWR is available at Aetrix Electronics and suitable for power tools, uninterruptible power supplies, light electric vehicles, and medical instrumentation requiring stable component supply, long-lifecycle support, and traceable sourcing for production programs.

Supply support for BQ34Z100PWR 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 decades of expertise in battery management and precision analog design.

The BQ34Z100PWR belongs to TI's Impedance Track™ fuel gauge product line, engineered specifically for high-accuracy, maintenance-free state-of-charge estimation in industrial, medical, and transportation battery systems operating across extreme voltage and temperature ranges.

FAQ

What battery chemistries does the BQ34Z100PWR support?

The BQ34Z100PWR natively supports Li-ion and LiFePO₄ chemistries through its Impedance Track™ algorithm. It accommodates custom chemistry configurations via programmable data flash, and its voltage translation architecture enables operation across 3 V–65 V battery stacks regardless of series-cell count. The BQ34Z100PWR does not support NiMH, lead-acid, or alkaline chemistries.

Does the BQ34Z100PWR require an external sense resistor?

Yes, the BQ34Z100PWR requires an external low-value shunt resistor connected between SRP and SRN pins to measure charge/discharge current. The device integrates the voltage across this resistor using its 14-bit coulomb counter ADC, with ±10 µV input offset and ±0.034% FSR INL. No internal sense FET or current mirror is present - accurate current measurement depends entirely on external resistor selection and layout.

How does the BQ34Z100PWR achieve <1% state-of-charge accuracy?

The BQ34Z100PWR achieves <1% SOC accuracy through Texas Instruments' patented Impedance Track™ algorithm, which correlates real-time battery impedance with open-circuit voltage (OCV) and temperature to model aging, self-discharge, and capacity fade. This method eliminates reliance on full-charge/full-discharge cycles and maintains accuracy across 500+ cycles and –40°C to 85°C without recalibration - a capability confirmed in TI's SLUSAU1C characterization data.

Can the BQ34Z100PWR operate without a host microcontroller?

Yes, the BQ34Z100PWR operates fully autonomously: it performs coulomb counting, Impedance Track™ modeling, temperature compensation, and aging updates independently. Host interaction is optional - used only for reading parameters (e.g., RemainingCapacity(), Voltage()) or configuring authentication keys. The BQ34Z100PWR continues gauging and updating flash-resident parameters even when I²C/HDQ lines are idle.

What is the role of the VEN pin on the BQ34Z100PWR?

The VEN pin on the BQ34Z100PWR is an active-high voltage translation enable signal that controls external resistor dividers used to scale high-voltage battery inputs (up to 65 V) down to the 0–5.5 V range accepted by the BAT pin. When VEN is deasserted, the divider is disabled, reducing quiescent current by ~45 µA - a critical feature for extending shelf life in sealed battery packs where the BQ34Z100PWR remains powered continuously.