Analog Devices Inc. LTC2942CDCB-1#TRMPBF

Overview

LTC2942CDCB-1#TRMPBF from Analog Devices (formerly Linear Technology) is a single-cell Li-Ion battery gas gauge IC with integrated 50 mΩ high-side sense resistor, 14-bit voltage ADC, and 10-bit temperature ADC. It measures accumulated charge (±1 A range), battery voltage (2.7 V to 5.5 V), and die temperature, delivering ±1% charge accuracy and 1% voltage accuracy. It is deployed in space-constrained portable electronics requiring precise state-of-charge monitoring without external sensing components.

For engineers reviewing the LTC2942CDCB-1#TRMPBF datasheet, LTC2942CDCB-1#TRMPBF pinout, LTC2942CDCB-1#TRMPBF application, or LTC2942CDCB-1#TRMPBF equivalent, key selection considerations include its internal sense resistor architecture, SMBus/I²C address (0x64), 6-pin DFN package, ±1 A current range, and programmable alert thresholds for charge/voltage/temperature - all critical for handheld power management design.

Technical Context

The LTC2942CDCB-1#TRMPBF implements a precision auto-zeroed differential analog integrator for coulomb counting, using its monolithic 50 mΩ sense resistor between SENSE+ and SENSE–. Its No Latency ΔΣ architecture enables 14-bit voltage and 10-bit temperature conversions with 15 ms typical conversion time, updated via I²C registers.

It operates in three configurable ADC modes (sleep, manual voltage, manual temperature, or automatic dual-scan), and supports dual-function AL/CC pin - either as SMBus-compliant open-drain alert output or as charge-complete logic input - controlled by B[2:1] bits in the control register.

Key Specifications

Pinout & Package

Package: 6-lead (2 mm × 3 mm) plastic DFN with exposed pad (Pin 7, not connected). Thermal performance optimized when exposed pad is soldered to isolated copper area.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BQ27426YZFT and MAX17048G+T, the LTC2942CDCB-1#TRMPBF uniquely combines internal 50 mΩ sensing, ±1 A range, and on-die temperature measurement in a 2 mm × 3 mm DFN - reducing BOM count and layout complexity for cost-sensitive, space-constrained single-cell applications.

Availability

LTC2942CDCB-1#TRMPBF is available at Aetrix Electronics and suitable for smartphone power management, portable GPS trackers, Bluetooth headsets, medical wearables, and industrial handheld terminals requiring stable component supply and guaranteed long-term sourcing.

Supply support for LTC2942CDCB-1#TRMPBF 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

Analog Devices, Inc. (ADI) is a global semiconductor leader specializing in high-performance analog, mixed-signal, and digital signal processing technologies.

The LTC2942 family was designed by Linear Technology (acquired by ADI in 2017) specifically for accurate, low-power battery fuel gauging in compact portable devices - emphasizing integration, measurement stability, and ease of I²C-based system integration.

FAQ

What is the operating temperature range for the LTC2942CDCB-1#TRMPBF?

The LTC2942CDCB-1#TRMPBF is specified for 0°C to 70°C ambient operation (C-grade). This range is validated per its Absolute Maximum Ratings and Electrical Characteristics tables, with parameters like total charge error (±1.8%) and voltage accuracy (±1.3%) guaranteed across this interval. The device's internal temperature sensor also reports die temperature with ±3 K total unadjusted error within this grade.

Does the LTC2942CDCB-1#TRMPBF require an external sense resistor?

No, the LTC2942CDCB-1#TRMPBF does not require an external sense resistor. It integrates a precision 50 mΩ high-side sense resistor between SENSE+ and SENSE– pins, rated for ±1 A continuous current. This eliminates layout sensitivity, thermal drift, and BOM cost associated with discrete shunts - a core differentiator confirmed in the "Integrated 50mΩ High Side Sense Resistor" feature and electrical characteristics table.

How is the I²C address configured for the LTC2942CDCB-1#TRMPBF?

The LTC2942CDCB-1#TRMPBF uses a fixed, hard-coded 7-bit I²C address of 0x64 (1100100b), as documented in the Applications Information section. There are no address pins or configuration options - the address is immutable and shared across all LTC2942-1 variants. This simplifies bus arbitration but requires careful system-level address mapping when multiple LTC2942-1 devices are present.

Can the LTC2942CDCB-1#TRMPBF measure battery temperature accurately in high-current conditions?

Yes, but with thermal self-heating consideration: the LTC2942CDCB-1#TRMPBF's on-die temperature sensor reports junction temperature (TDIE), which rises above ambient (TAMB) under load - e.g., +12 K at 1 A with recommended layout. For accurate battery temperature, the exposed pad should be thermally coupled to the battery can or PCB thermal plane, and software correction using measured current (from coulomb counter) can compensate for known thermal resistance.

What happens to the accumulated charge register during undervoltage lockout on the LTC2942CDCB-1#TRMPBF?

During undervoltage lockout (UVLO) - triggered when VSENSE+ falls below 2.7 V - the analog coulomb counter shuts down, but the accumulated charge register (ACR) retains its last valid value. Upon recovery above UVLO threshold, integration resumes from that stored value. However, charge flowing while VSENSE+ < 2.7 V is unmeasured and lost, as explicitly stated in the Status Register description and Power-Up Sequence section of the datasheet.