Texas Instruments BQ34Z110PW

Overview

BQ34Z110PW from Texas Instruments is a standalone fuel gauge IC for lead-acid battery packs, delivering state-of-charge (SoC) estimation with ≤1% error using patented Impedance Track™ technology. It operates across 4 V–64 V battery systems, supports >65 Ah capacity and >32 A charge/discharge currents, and integrates coulomb counting, temperature sensing, and SHA-1 authentication - deployed in UPS and light electric vehicles.

For engineers reviewing the BQ34Z110PW datasheet, BQ34Z110PW pinout, BQ34Z110PW application, or BQ34Z110PW equivalent, this page delivers verified technical context, real-world power-mode current values (<140 µA normal, <19 µA full sleep), I²C/HDQ interface timing, LED display control capability, and authentic alternative part comparisons - all grounded in TI's SLUSB55B revision May 2013 specification.

Technical Context

The BQ34Z110PW implements a dual-oscillator architecture: a 32.768 kHz low-frequency oscillator (±4% error over –40°C to 85°C) for timekeeping and a trimmed 8.389 MHz high-frequency oscillator (±4.5% error) for ADC and computation. Its integrating ADC provides 14–15-bit resolution for both coulomb counting (SRP/SRN inputs) and temperature/cell voltage measurement (TS/BAT inputs), with input offset ≤10 µV and effective input resistance ≥2.5 MΩ on sense inputs.

It executes Impedance Track™ algorithm autonomously - requiring no host intervention during runtime - and stores calibration data, chemistry profiles, and user parameters in 32 bytes of programmable data flash memory (10-year retention, 20,000 write cycles). Authentication uses SHA-1/HMAC via dedicated scratch pad, supporting both field-reprogrammable and TI-permanently-programmed keys.

Key Specifications

Pinout & Package

14-pin TSSOP package (PW suffix), 5.0 mm × 4.4 mm body, 0.65 mm pitch, exposed thermal pad (not electrically connected). Thermal resistance θJA = 103.8 °C/W (high-K board).

Key Features

Applications

Equivalent & Alternatives

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

Compared with BQ34Z110PW, BQ34Z100-G1 offers enhanced thermal range and integrated sensing but identical firmware compatibility, while MAX17205 provides superior Li-ion modeling but zero lead-acid support - making BQ34Z110PW the sole validated solution for cost-sensitive, wide-voltage lead-acid systems.

Availability

BQ34Z110PW is available at Aetrix Electronics and suitable for uninterruptible power supplies, light electric vehicles, medical instrumentation, and power tools requiring stable component supply, long-term lifecycle assurance, and TI-qualified lead-acid fuel gauging.

Supply support for BQ34Z110PW 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 - serving industrial, automotive, and communications markets since 1930.

The BQ34Z110PW belongs to TI's battery fuel gauge product line, engineered specifically for high-accuracy, autonomous state-of-charge estimation in lead-acid battery systems - emphasizing low-power operation, robust authentication, and chemistry-agnostic voltage range scalability.

FAQ

What battery chemistries does the BQ34Z110PW support?

The BQ34Z110PW is explicitly designed and validated for lead-acid battery chemistries - including flooded, AGM, and gel-cell types - and does not support lithium-ion, NiMH, or other chemistries. Its Impedance Track™ algorithm uses lead-acid-specific voltage-SoC and impedance models, and TI provides pre-characterized chemistry profiles in data flash for these variants. Using BQ34Z110PW with non-lead-acid cells will produce inaccurate SoC estimates.

Does the BQ34Z110PW require a microcontroller to operate?

No, the BQ34Z110PW operates autonomously: it runs the Impedance Track™ algorithm, manages power modes (NORMAL/SLEEP/FULL SLEEP), performs coulomb counting, and updates SoC without host intervention. A microcontroller is only needed to read results (e.g., RemainingCapacity()) via I²C or HDQ, configure initial settings, or trigger calibration - not for core fuel gauging functionality.

What is the maximum battery voltage the BQ34Z110PW can monitor directly?

The BQ34Z110PW cannot monitor battery voltage directly above 5.5 V on its BAT pin. To support 4 V–64 V battery systems, an external voltage translation circuit (e.g., resistor divider + FET switch controlled by VEN) is required. The device automatically manages this circuit via the VEN pin to minimize divider power consumption - a key design feature confirmed in TI's SLUSB55B datasheet.

How does the BQ34Z110PW handle temperature measurement?

The BQ34Z110PW supports two temperature sources: an external 103AT-type NTC thermistor connected to the P6/TS pin (default), or its internal temperature sensor. Selection is controlled by the [TEMPS] bit in the Pack Configuration register. The TS input accepts 0.05 V–1 V with 8 MΩ input resistance, enabling direct interface with common thermistor networks without additional signal conditioning.

Can the BQ34Z110PW be used in sealed battery packs without external access?

Yes - the BQ34Z110PW supports SEALED mode, which locks configuration registers and disables write access to prevent tampering. In SEALED mode, the device continues full fuel gauging operation and reports SoC, voltage, and temperature via I²C or HDQ. Authentication (SHA-1/HMAC) further ensures pack integrity, making BQ34Z110PW suitable for consumer-facing sealed battery modules.