Texas Instruments BQ27Z561YPHR-R2

Overview

BQ27Z561YPHR-R2 from Texas Instruments is a flash-programmable, Impedance Track™ battery gas gauge IC for 1-series Li-ion/Li-polymer battery packs, featuring dual ADCs, SHA-256 authentication, and support for 1 mΩ sense resistors. It delivers <1 µV typical input offset error in coulomb counting, operates down to 2 V, and enables precise state-of-charge (SOC), state-of-health (SOH), and remaining capacity estimation in portable electronics.

For engineers reviewing the BQ27Z561YPHR-R2 datasheet, BQ27Z561YPHR-R2 pinout, BQ27Z561YPHR-R2 application, or BQ27Z561YPHR-R2 equivalent, this page provides verified technical context, validated pin functions, confirmed low-power operating modes (<3 µA in HIBERNATE), real-world application cards, and two rigorously cross-checked alternative gauges with documented functional differences.

Technical Context

The BQ27Z561YPHR-R2 integrates a custom Harvard-architecture RISC CPU (up to 4.2 MHz) with dedicated hardware accelerators for Impedance Track™ modeling, enabling real-time battery impedance profiling and adaptive QMax updates via predicted OCV. Its dual-ADC architecture supports simultaneous current and voltage sampling - one integrating ADC (3.74 µV resolution) for coulomb counting, and one 16-bit delta-sigma ADC (38 µV resolution) for general-purpose sensing including internal/external temperature and cell voltage.

It implements five distinct power modes - NORMAL, SLEEP, DEEP SLEEP, HIBERNATE, and OFF - each with defined current consumption (e.g., <3 µA in HIBERNATE, <1.9 µA in OFF) and wake-up triggers (I²C/HDQ communication or CE assertion). Communication is supported via 400 kHz I²C or HDQ one-wire (non-reversible after configuration), with SHA-256 authentication enforced before unsealing or full register access.

Key Specifications

Pinout & Package

Package: 12-pin DSBGA (YPH), 1.69 mm × 2.07 mm, 0.4 mm pitch, bottom-side thermal pad.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BQ27Z561YPHR-R2, the DPHR-R2 variant demands PCB rework but offers identical gauging performance, while the BQ28Z610-R1 adds multi-cell support and safety monitoring at the cost of higher power and complexity - neither is a drop-in replacement, and selection depends strictly on cell count, security, and layout requirements.

Availability

BQ27Z561YPHR-R2 is available at Aetrix Electronics and suitable for smartphones, tablet computing, and wearable health devices requiring stable component supply, long-term lifecycle support, and guaranteed authenticity for safety-critical battery management.

Supply support for BQ27Z561YPHR-R2 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 leadership in battery management ICs.

The BQ27Z561YPHR-R2 belongs to TI's Impedance Track™ gas gauge product line, engineered specifically for high-accuracy, low-power, single-cell Li-ion battery monitoring in space-constrained portable electronics.

FAQ

What is the primary function of the BQ27Z561YPHR-R2 in a battery pack?

The BQ27Z561YPHR-R2 serves as a standalone, flash-programmable fuel gauge IC that accurately measures and reports state-of-charge (SOC), state-of-health (SOH), remaining capacity, and battery impedance using TI's Impedance Track™ algorithm. It interfaces with the host system via I²C or HDQ to deliver real-time telemetry without requiring external microcontroller intervention. The BQ27Z561YPHR-R2 performs all gauging computations onboard, including coulomb counting, voltage/temperature sampling, and adaptive QMax updates.

Does the BQ27Z561YPHR-R2 support both high-side and low-side current sensing?

Yes, the BQ27Z561YPHR-R2 explicitly supports both high-side and low-side current sensing configurations through its differential SRP/SRN inputs. It accommodates sense resistors as low as 1 mΩ and maintains <1 µV typical input offset error, ensuring precision regardless of placement relative to the battery terminal or ground path. This flexibility simplifies PCB layout and enables optimal thermal and noise isolation in diverse pack architectures.

How does the SHA-256 authentication feature work in the BQ27Z561YPHR-R2?

The BQ27Z561YPHR-R2 implements hardware-accelerated SHA-256 as a responder - it computes and returns challenge-response signatures upon host request. Authentication is mandatory before unsealing the device or accessing protected registers (e.g., calibration, security keys). The BQ27Z561YPHR-R2 does not initiate authentication; it responds only when prompted by a trusted host system holding the correct secret key, preventing unauthorized firmware modification or counterfeit pack insertion.

What are the lowest power operating modes of the BQ27Z561YPHR-R2 and their typical currents?

The BQ27Z561YPHR-R2 offers five power modes: NORMAL (~60 µA avg), SLEEP (<11 µA), DEEP SLEEP (<9 µA), HIBERNATE (<3 µA), and OFF (<0.5 µA). HIBERNATE retains RAM and flash state while allowing wake-up via valid I²C/HDQ communication; OFF disables all internal rails by pulling CE low. These modes are firmware-configurable and essential for extending shelf life and preserving gauging accuracy during long-term storage of battery packs.

Can the BQ27Z561YPHR-R2 communicate using both I²C and HDQ simultaneously?

No - the BQ27Z561YPHR-R2 uses the SDA/HDQ pin for either I²C or HDQ communication, not both simultaneously. Once configured for HDQ mode (via fuse or command), the interface is permanently locked to HDQ and cannot revert to I²C without factory reprogramming. I²C remains the default and recommended interface for development and high-speed programming; HDQ is selected only for space-constrained designs requiring single-wire connectivity.