Analog Devices Inc. LTC4007EUFD-1#PBF

Overview

LTC4007EUFD-1#PBF from Analog Devices (formerly Linear Technology) is a synchronous constant-current/constant-voltage battery charger controller for 3- or 4-cell Li-ion packs, featuring ±0.8% float voltage accuracy, programmable 4A charging current (±4%), and thermistor-based temperature qualification. It operates across 6V–28V input, delivers up to 96% efficiency, and integrates AC adapter current limiting for optimized charge rate in portable power systems.

For engineers reviewing the LTC4007EUFD-1#PBF datasheet, LTC4007EUFD-1#PBF pinout, LTC4007EUFD-1#PBF application, or LTC4007EUFD-1#PBF equivalent, key selection criteria include its 24-pin 4mm × 5mm QFN package, dual cell-count/chemistry configuration pins (3C4C/CHEM), integrated C/10 termination, and ±100mV input current limit threshold with ICL indicator output.

Technical Context

The LTC4007EUFD-1#PBF implements a constant-off-time, current-mode synchronous buck architecture with quasi-constant frequency operation (255–345 kHz), enabling silent ceramic-capacitor designs. Its inner-loop control uses ITH voltage to regulate peak inductor current via external MOSFETs driven by TGATE and BGATE outputs.

It integrates dual feedback paths: CA1 senses CSP–BAT for current regulation, while EA compares a precision internal resistor divider on BAT against a 1.19V reference for voltage regulation. Thermistor sampling occurs at fixed intervals (e.g., 42–60 ms with R_RT = 1190kΩ), with high/low thresholds set by NTCVR × 0.48–0.52 and × 0.115–0.135 respectively.

Key Specifications

Pinout & Package

Package: 24-lead plastic QFN (4mm × 5mm), exposed pad (Pin 25) must be connected to GND and PGND with low-ohmic thermal path.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Li-ion battery charger controller applications.

Compared with BQ24725ARHBT and MP2759GQZ, the LTC4007EUFD-1#PBF uniquely combines autonomous thermistor qualification, RT-programmable charge timing, and dual 3/4-cell/4.1/4.2V configuration in a single 4mm × 5mm QFN - making it optimal for industrial and medical Li-ion chargers requiring hardware-level safety and flexibility without microcontroller dependency.

Availability

LTC4007EUFD-1#PBF is available at Aetrix Electronics and suitable for notebook computers, portable instruments, battery-backup systems, and medical Li-ion chargers requiring stable component supply, long-lifecycle support, and guaranteed parametric performance over –40°C to +85°C.

Supply support for LTC4007EUFD-1#PBF 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 acquired Linear Technology in 2017 and maintains its legacy of high-performance analog ICs for precision power, signal conditioning, and timing applications.

The LTC4007EUFD-1#PBF belongs to Linear's battery management controller product line, designed specifically for high-efficiency, thermally robust, and configuration-flexible Li-ion charging in portable and industrial systems where reliability and safety are non-negotiable.

FAQ

What is the function of the RT pin on the LTC4007EUFD-1#PBF?

The RT pin on the LTC4007EUFD-1#PBF connects to an external resistor to ground that sets the total charge time using t_TIMER = 1 hour × R_RT/154kΩ. This resistor is mandatory - absence prevents charger startup. For example, a 309kΩ resistor yields ~2 hours total charge time. The LTC4007EUFD-1#PBF samples this resistor to schedule termination and supports timer defeat via CHG pin override.

How does the LTC4007EUFD-1#PBF configure 3-cell vs. 4-cell battery packs?

The LTC4007EUFD-1#PBF uses the 3C4C pin to select float voltage: grounding it configures 12.6V (3-cell), while leaving it open configures 16.8V (4-cell). This adjusts the internal resistor divider on the BAT pin. The CHEM pin further selects 4.1V/cell (grounded) or 4.2V/cell (open), enabling four precise float voltages (12.3V, 12.6V, 16.4V, 16.8V) with ±0.8% accuracy - all without external components.

Does the LTC4007EUFD-1#PBF support thermistor-based temperature monitoring?

Yes, the LTC4007EUFD-1#PBF integrates a dedicated NTC pin (Pin 7) with internal sampling circuitry that measures thermistor voltage at regular intervals (e.g., 42–60 ms). It compares sampled values against high/low thresholds derived from a 4.5V reference and asserts FAULT if out-of-range. The LTC4007EUFD-1#PBF suspends charging automatically and resumes when temperature returns to safe limits - no host processor required.

What is the purpose of the PROG pin on the LTC4007EUFD-1#PBF?

The PROG pin on the LTC4007EUFD-1#PBF serves dual functions: programming peak charge current via an external resistor to ground (R_PROG), and providing a voltage output linearly proportional to actual charge current (0.3V at 0A, 1.19V at full scale). This allows real-time current monitoring without additional amplifiers. The LTC4007EUFD-1#PBF achieves ±4% current accuracy, and R_PROG values >100kΩ will cause shutdown.

Can the LTC4007EUFD-1#PBF operate with ceramic output capacitors without audible noise?

Yes, the LTC4007EUFD-1#PBF uses a synchronous, quasi-constant-frequency, constant-off-time PWM architecture (255–345 kHz) that avoids sub-audible switching frequencies. Combined with its integrated watchdog timer that prevents dropout oscillation, the LTC4007EUFD-1#PBF enables silent operation with ceramic input/output capacitors - eliminating the need for noisy tantalum or electrolytic alternatives in noise-sensitive applications.