Analog Devices Inc. LTC4071IMS8E#TRPBF

Overview

LTC4071IMS8E#TRPBF from Analog Devices is a Li-ion/polymer shunt battery charger IC with integrated low-battery disconnect, thermal qualification via NTC, and programmable 4.0V/4.1V/4.2V float voltage (±1% accuracy). It operates from 550nA quiescent current, supports up to 50mA internal shunt current, and delivers near-zero leakage (<0.01nA) battery disconnect - enabling energy harvesting, thin-film battery backup, and solar-powered memory retention.

For engineers reviewing the LTC4071IMS8E#TRPBF datasheet, LTC4071IMS8E#TRPBF pinout, LTC4071IMS8E#TRPBF application, or LTC4071IMS8E#TRPBF equivalent, this page provides verified pin functions, thermal-aware float voltage behavior, low-power NTC sampling architecture, and real-world disconnect thresholds (2.7V/3.2V) confirmed for the MS8E package across –40°C to 125°C.

Technical Context

The LTC4071IMS8E#TRPBF implements a shunt-based charging architecture where input current flows through an external resistor (R_IN) into the battery via the internal PFET body diode until V_CC exceeds VLBC_VCC (3.6V typical), at which point MP1 turns on to reconnect BAT–VCC. Its 3-state ADJ pin decoder selects float voltage (GND=4.0V, floating=4.1V, VCC=4.2V), while NTC monitoring uses pulsed 30–200µs biasing of NTCBIAS at ~1.2s intervals to minimize power draw.

Low-battery protection relies on dual threshold detection: falling V_BAT triggers disconnect at 2.7V (LBSEL=VCC) or 3.2V (LBSEL=GND), with hysteresis ensuring stable reconnection at VLBC_BAT (2.97V/3.53V). The HBO output asserts high when V_CC rises within 15–75mV of the effective float voltage (VFLOAT_EFF), including NTC-induced reductions down to 3.8V minimum.

Key Specifications

Pinout & Package

Package: 8-lead plastic MSOP (MS8E), 3mm × 3mm, 0.75mm profile, exposed pad (Pin 9) soldered to PCB ground for thermal performance (θ_JA = 40°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar shunt battery charger applications.

Compared with MAX1555 and BQ24040, the LTC4071IMS8E#TRPBF uniquely combines 550nA quiescent operation, NTC-based thermal derating, and <0.01nA disconnect leakage-making it the only viable choice for decade-scale energy harvesting and mission-critical backup where battery longevity and micro-power operation are mandatory.

Availability

LTC4071IMS8E#TRPBF is available at Aetrix Electronics and suitable for energy harvesting systems, solar-powered memory backup, and embedded automotive telematics requiring stable component supply with guaranteed long-term availability and traceable sourcing.

Supply support for LTC4071IMS8E#TRPBF 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 is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving precision instrumentation, industrial automation, communications, and automotive markets.

The LTC4071 belongs to Analog Devices' Power Management product line, designed specifically for ultra-low-power battery charging and protection in energy-constrained environments such as IoT edge nodes and maintenance-free backup systems.

FAQ

What is the maximum shunt current capability of the LTC4071IMS8E#TRPBF?

The LTC4071IMS8E#TRPBF supports a maximum internal shunt current of 50mA. This value is specified under V_CC > V_FLOAT conditions and defines the upper limit of current the device can divert away from the battery to maintain regulated float voltage. Exceeding this current risks thermal overload, especially in the MS8E package where θ_JA = 40°C/W.

How does the LTC4071IMS8E#TRPBF implement thermal qualification of the float voltage?

The LTC4071IMS8E#TRPBF samples the NTC pin against four internal voltage thresholds (NTCTH1–NTCTH4) tied to a pulsed NTCBIAS reference. When the NTC voltage falls below successive thresholds-corresponding to battery temperatures above 40°C, 50°C, 60°C, and 70°C-the device reduces V_FLOAT in fixed steps: 50mV (ADJ=GND), 75mV (ADJ=open), or 100mV (ADJ=VCC) per 10°C increment, down to a minimum of 3.8V.

Can the LTC4071IMS8E#TRPBF be used with batteries other than Li-ion or Li-polymer?

No-the LTC4071IMS8E#TRPBF is specifically designed for single-cell Li-ion and Li-polymer batteries. Its float voltage range (4.0–4.2V), low-battery thresholds (2.7V/3.2V), and NTC qualification algorithm are calibrated for these chemistries. Using it with NiMH, lead-acid, or LiFePO₄ cells would result in overcharging, undercharging, or incorrect thermal response due to mismatched voltage profiles and temperature coefficients.

What is the purpose of the HBO pin on the LTC4071IMS8E#TRPBF?

The HBO (High Battery Output) pin on the LTC4071IMS8E#TRPBF is a CMOS-compatible active-high signal that asserts when V_CC rises to within V_HBTH (15–75mV) of the effective float voltage V_{FLOAT_EFF}. It indicates near-full battery charge and enables system-level actions such as disabling auxiliary loads or initiating data logging. Its VOH = VCC–0.6V and VOL = 0.5V support direct interfacing with most MCUs.

Does the LTC4071IMS8E#TRPBF require external components beyond R_IN?

Yes-the LTC4071IMS8E#TRPBF requires at minimum an input resistor R_IN and a 0.1µF decoupling capacitor from VCC to GND. For NTC functionality, a 10kΩ bias resistor (RNOM) from NTCBIAS to NTC and a Vishay NTHS0402N02N1002F thermistor from NTC to GND are needed. The ADJ and LBSEL pins must be hard-wired to GND, VCC, or left open (ADJ only)-floating LBSEL is prohibited.