Analog Devices Inc. LTC2941CDCB-1#TRMPBF

Overview

LTC2941CDCB-1#TRMPBF from Analog Devices (formerly Linear Technology) is a single-cell Li-Ion battery gas gauge IC with integrated 50mΩ high-side sense resistor, ±1A current sensing range, 1% total charge accuracy, and SMBus/I²C interface. It measures accumulated charge/discharge in handheld PCs, cellular phones, and GPS devices by integrating current through its internal resistor between battery positive terminal and load/charger.

For engineers reviewing the LTC2941CDCB-1#TRMPBF datasheet, LTC2941CDCB-1#TRMPBF pinout, LTC2941CDCB-1#TRMPBF application, or LTC2941CDCB-1#TRMPBF equivalent, key selection considerations include its 2.7V–5.5V operating range, 6-pin 2mm × 3mm DFN package, programmable charge thresholds, alert/charge-complete dual-mode AL/CC pin, and factory-trimmed 50mΩ sense resistor with <±50ppm/K tempco.

Technical Context

The LTC2941CDCB-1#TRMPBF implements a precision auto-zeroed differential analog integrator that converts voltage across its internal 50mΩ sense resistor into accumulated charge, stored in 16-bit registers C/D. Its coulomb counter uses a programmable prescaler (M = 1 to 128) to scale integration time and achieve 0.085mAh LSB at default M=128.

It features dual-function AL/CC pin configurable via control register B[2:1] as either SMBus-compliant open-drain alert output or charge-complete digital input; status flags (A[3], A[2], A[1]) indicate threshold exceedance, overflow/underflow, or V_BAT drop below 2.75–3.05V thresholds selected by B[7:6].

Key Specifications

Pinout & Package

Package: 6-lead 2mm × 3mm plastic DFN (DCB) with exposed pad (Pin 7, do not connect). 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, LTC2941CDCB-1#TRMPBF delivers lower system-level BOM cost and smaller footprint via integrated sensing, while LTC2942CDCB-1#TRMPBF offers direct upgrade path with enhanced voltage resolution and temperature range-both alternatives require no PCB redesign but differ in algorithmic capability and environmental robustness.

Availability

LTC2941CDCB-1#TRMPBF is available at Aetrix Electronics and suitable for smartphone battery management, portable GPS trackers, and Bluetooth headset power systems requiring stable component supply, consistent parametric performance, and long-term production continuity.

Supply support for LTC2941CDCB-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 for precision measurement and power management.

The LTC2941CDCB-1#TRMPBF belongs to ADI's Linear Technology legacy battery management product line, engineered specifically for compact, low-power portable electronics requiring accurate single-cell Li-Ion gas gauging without external components.

FAQ

What is the maximum continuous sense current supported by the LTC2941CDCB-1#TRMPBF?

The LTC2941CDCB-1#TRMPBF supports ±1A continuous DC sense current under normal operation, with ±2A absolute maximum rating. This range covers typical peak loads in smartphones, GPS units, and headsets. Exceeding ±1A continuously may increase total charge error beyond the specified ±1% and accelerate internal sense resistor aging-designs requiring >1A should verify thermal derating per the datasheet's power dissipation guidelines.

How does the LTC2941CDCB-1#TRMPBF handle power supply brownouts below 2.7V?

When V_SENSE+ drops below 2.7V, the LTC2941CDCB-1#TRMPBF asserts the undervoltage lockout (UVLO) flag (A[0]) and disables analog circuitry while retaining digital register contents. The coulomb counter stops integrating during the brownout; upon recovery above 2.7V, it resumes with the stored accumulated charge value-but all charge flow during the UVLO period is unmeasured. For critical applications, use the V_BAT alert feature to proactively warn before UVLO occurs.

Can the LTC2941CDCB-1#TRMPBF be used with batteries other than single-cell Li-Ion?

Yes-the LTC2941CDCB-1#TRMPBF operates from 2.7V to 5.5V and supports any battery chemistry within that voltage range, including Li-Polymer, NiMH, and certain lead-acid configurations. Its ±1A current range and 1% charge accuracy remain valid, but application-specific calibration of V_BAT thresholds and charge termination logic is required since the device does not perform chemistry identification or adaptive learning like advanced fuel gauges.

What is the purpose of the exposed pad (Pin 7) on the LTC2941CDCB-1#TRMPBF DFN package?

The exposed pad (Pin 7) on the LTC2941CDCB-1#TRMPBF is electrically isolated and must not be connected to any net. Its sole purpose is thermal conduction: soldering it to a large, isolated copper pour significantly reduces θ_JA from 160°C/W to <60°C/W, preventing thermal shutdown during sustained ±1A operation. Leaving it unconnected degrades thermal performance but does not impair electrical functionality.

How is the accumulated charge register (C/D) read correctly to avoid data corruption?

To prevent corruption, the LTC2941CDCB-1#TRMPBF accumulated charge register must be read in a single I²C transaction: issue START → slave address (0x64) + write bit → register address 0x02 → repeated START → slave address + read bit → read two bytes (C then D) → STOP. Reading C and D in separate transactions risks mid-read updates due to ongoing coulomb counting, causing inconsistent 16-bit values. The device does not support auto-incrementing reads across non-adjacent registers.