Texas Instruments BQ27742YZFR-G1 — Single‑cell Li‑ion Fuel Gauge with Impedance Track, I2C/SMBus, 12‑Ball DSBGA
The Texas Instruments BQ27742YZFR-G1 is a high‑accuracy, single‑cell battery fuel gauge designed for compact, battery‑powered products that need dependable state‑of‑charge (SOC) and state‑of‑health (SOH) reporting. Built on TI’s proven Impedance Track algorithm and communicating over an I2C/SMBus‑compatible interface, the BQ27742‑G1 delivers reliable gauging for 1S (single series cell) Li‑ion and Li‑polymer packs. Its 12‑ball DSBGA (YZF) package enables tight integration in space‑constrained designs such as wearables, handhelds, and IoT devices.
At a Glance
- Manufacturer/Brand: Texas Instruments
- Series: BQ27742‑G1
- MPN: BQ27742YZFR‑G1
- Category: Battery Fuel Gauge ICs
- Battery Chemistry: Single‑cell Li‑ion/Li‑polymer
- Cells Supported: 1S (single series cell)
- Fuel‑Gauge Algorithm: Impedance Track
- Interface: I2C / SMBus‑compatible
- Package: DSBGA‑12 (TI package code YZF)
- Packaging: Tape & Reel (suffix YZFR)
- Mounting Type: Surface Mount
- Pin Count: 12
Why Choose the Texas Instruments BQ27742YZFR‑G1?
Accurate battery gauging is essential for modern portable products. From preventing unexpected shutdowns to optimizing runtime and charge cycles, the quality of your gauge directly influences user experience and product longevity. The Texas Instruments BQ27742YZFR‑G1 stands out by combining TI’s Impedance Track algorithm with integrated voltage, current, and temperature measurement. This combination helps deliver consistent SOC and SOH reporting across changing loads and over the battery’s service life.
- Proven algorithmic gauging: Impedance Track dynamically accounts for cell characteristics, aging, and operating conditions to help maintain accuracy over time.
- Complete measurement path: Integrated sensing of voltage, current, and temperature streamlines the design and simplifies host processing.
- Small, board‑friendly package: The 12‑ball DSBGA (YZF) footprint enables compact layouts and product miniaturization.
- Host‑friendly communications: I2C/SMBus‑compatible interface allows straightforward integration with common microcontrollers and processors.
These strengths make the BQ27742YZFR‑G1 a reliable choice when you need trustworthy SOC/SOH, robust capacity estimates, and space‑efficient implementation in a single‑cell architecture.
Key Specifications
The following specifications are provided directly from the available product data for the Texas Instruments BQ27742YZFR‑G1:
- Battery chemistry: Single‑cell Li‑ion/Li‑polymer
- Cells supported: 1S (single series cell)
- Fuel‑gauge algorithm: Impedance Track
- Interface: I2C / SMBus‑compatible
- Package code: YZF (DSBGA‑12)
- Pin count: 12
- Mounting type: Surface Mount
- Packaging: Tape & Reel (YZFR)
Not specified in datasheet (from provided data):
- Operating temperature range
- Power consumption (idle/sleep/active)
- Data rate or bus timing beyond I2C/SMBus compatibility
For any parameters not listed here, refer to the Texas Instruments datasheet and product page linked below.
Applications
The BQ27742YZFR‑G1 is well‑suited for a broad range of single‑cell designs that demand accurate fuel gauging in a compact footprint:
- Smartphones and tablets
- Wearables and fitness devices
- Portable medical and industrial handhelds
- IoT sensors and asset trackers
- Power banks and single‑cell battery packs
In each of these use cases, predictable SOC and SOH reporting help prevent unplanned downtime, enable graceful shutdowns, and improve end‑user confidence.
How the Impedance Track Approach Helps Your Product
Impedance Track is Texas Instruments’ established gauging methodology used across many of their fuel‑gauge families. For the BQ27742YZFR‑G1, it provides several practical benefits:
- Tracks cell behavior over life: As Li‑ion cells age, internal characteristics change. Impedance Track helps the gauge adapt to these changes so SOC and SOH estimates remain meaningful.
- Works across dynamic loads: Real‑world usage often involves bursts of current and changing operating conditions. Impedance Track helps maintain SOC accuracy during transient loads.
- Reduces guesswork for the host: With integrated voltage, current, and temperature measurement, the device presents the host with robust gauging data without requiring external estimation schemes.
The result is a consistent, dependable user experience—especially important in products where a dead battery can disrupt workflows or compromise a critical task.
Design and Integration Considerations
While the BQ27742YZFR‑G1 simplifies gauging, careful system design ensures you get the most from the device.
System Interface (I2C/SMBus)
- Connect the fuel gauge to your host via the I2C/SMBus‑compatible interface.
- Maintain adequate bus pull‑ups and signal integrity per your system design rules.
- Design your firmware to periodically read SOC, SOH, remaining capacity, voltage, current, and temperature to inform power‑management decisions, user interface, and system logging.
Measurement Path and Sensing
- The device integrates measurement of voltage, current, and temperature. Follow the datasheet’s guidance on connecting measurement lines and any recommended sensing components.
- Keep sense traces short and routed away from noisy nets where possible. Good PCB practice improves measurement stability.
Thermal and Mechanical Considerations
- The 12‑ball DSBGA (YZF) package is optimized for small form factors. Adhere to TI’s recommended land pattern, solder stencil, and reflow profile to ensure sound assembly.
- Consider board stack‑up and component placement to minimize thermal gradients around the gauge and battery sense circuitry.
Firmware and System Behavior
- Plan your power‑management policies based on SOC/SOH and remaining capacity readings. For example, trigger low‑battery notifications or gracefully persist data as capacity approaches a defined threshold.
- If your system logs mission‑critical events, consider storing both the instantaneous SOC and SOH to monitor pack aging over field life.
Note: For specific electrical limits, register maps, calibration procedures, or configuration flows, consult the official Texas Instruments datasheet (link below). Those details are not included in the provided data and should be implemented per TI’s documentation.
Ordering and Packaging Details
- Full MPN: BQ27742YZFR‑G1
- Package: DSBGA‑12 (TI package code YZF)
- Packaging: Tape & Reel (suffix YZFR)
- Mounting: Surface Mount
- Series: BQ27742‑G1
MPN decoding notes:
- YZF = 12‑ball DSBGA package
- R = Tape & Reel supply
- –G1 = chemistry profile version (per provided notes)
These details streamline procurement and ensure you receive the correct package and revision for your design.
Lifecycle, Availability, and Replacements
- Lifecycle status: Active (per Texas Instruments product page reference in the provided data)
- Availability: Check TI and authorized distributors for current availability and lead times
- Replacements: Not specified in the provided data
- Approved alternates: Not specified
When sourcing the Texas Instruments BQ27742YZFR‑G1, confirm date codes, packaging (YZFR), and handling requirements with your distributor. For lifecycle planning, monitor TI’s product page for change notifications and any announced next‑generation devices.
Compliance and Environmental
- RoHS / Environmental: Not specified in datasheet (based on provided data)
- REACH or other environmental statements: Not specified in the provided data
If your project requires formal environmental compliance documentation, request the latest compliance certificates from Texas Instruments or their authorized distribution partners.
Practical Tips for a Smooth Design‑In
- Start early with evaluation: Use early prototypes to validate SOC/SOH behavior under representative loads and temperatures.
- Plan for manufacturing variation: Ensure your test plan verifies bus communication and basic gauging functionality during production.
- Document field behavior: Capture SOC/SOH telemetry in logs during validation to correlate gauge readings with real‑world usage profiles.
- Keep firmware upgradable: Allow for updates that refine power‑management decisions based on observed gauging data across your device fleet.
These non‑spec tips can reduce iterations and speed time‑to‑market without changing your electrical design.
Frequently Asked Questions (FAQs)
Q: What battery types does the Texas Instruments BQ27742YZFR‑G1 support?
A: Single‑cell (1S) Li‑ion and Li‑polymer batteries.
Q: What interface does the device use to communicate with the host?
A: An I2C/SMBus‑compatible interface.
Q: What package is BQ27742YZFR‑G1 supplied in?
A: A 12‑ball DSBGA package (TI package code YZF) supplied in Tape & Reel format (suffix YZFR).
Q: Does the BQ27742YZFR‑G1 support multi‑cell (2S, 3S, etc.) packs?
A: No. It is designed for single‑cell (1S) applications only.
Q: What algorithm does the gauge use for SOC/SOH estimation?
A: Texas Instruments’ Impedance Track algorithm.
Q: Does the device measure voltage, current, and temperature internally?
A: Yes. The BQ27742‑G1 integrates measurement of voltage, current, and temperature, simplifying system design.
Q: What is the operating temperature range?
A: Not specified in the provided data. Refer to the TI datasheet for exact ratings.
Q: Are there drop‑in replacements identified for this part?
A: No direct replacements are specified in the provided data. Review TI’s portfolio for related single‑cell gauges if you require alternates.
Resources
- Product Page: https://www.ti.com/product/BQ27742-G1
- Datasheet: https://www.ti.com/lit/ds/symlink/bq27742-g1.pdf
For the most current specifications, configuration guidance, and application details, always consult the official Texas Instruments documentation.
Summary
The Texas Instruments BQ27742YZFR‑G1 brings dependable, algorithm‑driven fuel gauging to single‑cell Li‑ion/Li‑polymer designs. With Impedance Track at its core, integrated measurement capabilities, and an I2C/SMBus‑compatible interface, it helps engineering teams achieve predictable SOC and SOH without adding significant board area. The compact DSBGA‑12 (YZF) package and Tape & Reel (YZFR) availability make it a practical choice for high‑volume portable products. For parameters not listed above—such as detailed electrical limits, temperature range, and configuration—refer to the TI datasheet and product page before finalizing your design.