Analog Devices Inc. LTC4052EMS8E-4.2#TRPBF

Overview

LTC4052EMS8E-4.2 from Analog Devices (formerly Linear Technology) is a standalone 1-cell lithium-ion pulse charger IC with integrated 0.35Ω N-MOSFET, ±1% 4.2V float voltage accuracy, programmable timer-based charge termination, and C/10 near-end-of-charge detection. It operates from 4.5V to 10V input, delivers up to 1A charge current, and targets compact portable devices requiring minimal external components.

For engineers reviewing the LTC4052EMS8E-4.2 datasheet, LTC4052EMS8E-4.2 pinout, LTC4052EMS8E-4.2 application, or LTC4052EMS8E-4.2 equivalent, key selection criteria include its integrated MOSFET eliminating external blocking diodes, sense-resistor–based overcurrent protection, thermal shutdown, automatic trickle/refresh charging, and MSOP-8 exposed-pad package for thermal management.

Technical Context

The LTC4052EMS8E-4.2 implements a constant-current/constant-voltage (CC/CV) pulse charging algorithm using an internal charge pump–driven N-MOSFET switch. Charge current is set by the wall adapter's current limit and externally enforced via R_SENSE, with overcurrent trip at 105mV (±15mV). Timer duration scales linearly with C_TIMER, setting total charge time, minimum ON/OFF periods, and 640ms overcurrent retry interval.

It features three operational modes: trickle charge (<2.45V battery), full CC/CV pulsing (2.45V–4.2V), and sleep mode (VIN–VBAT <45mV). C/10 detection monitors GATE duty cycle to activate weak 40µA CHRG pulldown; ACPR provides open-drain wall adapter presence indication; BAT pin is internally clamped to 4.7V during disconnect.

Key Specifications

Pinout & Package

The LTC4052EMS8E-4.2 is housed in an 8-pin thermally enhanced MSOP package (MS8E) with exposed ground pad soldered to PCB for optimal heat dissipation (θ_JA = 35°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar lithium-ion battery charging applications.

Compared with LTC4054ES5-4.2#TRMPBF, the LTC4052EMS8E-4.2 offers higher 1A current and external current limiting via R_SENSE, while LTC1731CMS8-4.2#PBF provides controller-level flexibility at the cost of added components and layout effort-neither is pin-compatible, but all three serve distinct trade-offs in integration, power, and thermal control.

Availability

LTC4052EMS8E-4.2 is available at Aetrix Electronics and suitable for handheld computers, cellular telephones, and cradle chargers requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for LTC4052EMS8E-4.2 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 precision analog and power management product lines with rigorous qualification and long-term support.

The LTC4052EMS8E-4.2 belongs to Linear's standalone Li-ion charger IC family, designed specifically for compact, low-component-count battery charging in portable consumer and medical electronics without microcontroller dependency.

FAQ

What is the maximum input voltage rating for the LTC4052EMS8E-4.2?

The LTC4052EMS8E-4.2 has an absolute maximum input supply voltage (VIN) rating of 12V. Its recommended operating range is 4.5V to 10V, aligning with standard wall adapters. Exceeding 12V risks permanent damage per Absolute Maximum Ratings. The device includes internal clamping on GATE (12V above GND) and BAT (4.7V), but VIN itself must remain within specification to ensure reliability and longevity of the LTC4052EMS8E-4.2.

How does the LTC4052EMS8E-4.2 handle overcurrent protection?

The LTC4052EMS8E-4.2 implements overcurrent protection via the SENSE pin: when voltage across the external R_SENSE exceeds 105mV (±15mV), the internal MOSFET immediately turns off and remains off for 640ms before retrying. This limits average current to ~1% of the overcurrent value when CTIMER = 0.1µF. If overcurrent protection is unnecessary, SENSE may be shorted to VIN. This behavior is intrinsic to the LTC4052EMS8E-4.2 and requires no external logic or supervision.

Can the LTC4052EMS8E-4.2 be used with batteries other than 4.2V Li-ion?

No-the LTC4052EMS8E-4.2 is factory-trimmed for a fixed 4.2V float voltage and is not adjustable. Its internal resistor divider and reference are optimized exclusively for single-cell Li-ion chemistry. Using it with LiFePO₄ (3.6V), Li-polymer variants, or multi-cell stacks violates specifications and risks undercharging or overvoltage. For alternate chemistries, select purpose-built parts like LTC4053 (USB-compatible) or LTC1733 (thermal-regulated), not the LTC4052EMS8E-4.2.

What is the function of the ACPR pin on the LTC4052EMS8E-4.2?

The ACPR pin on the LTC4052EMS8E-4.2 is an open-drain output that pulls low when VIN exceeds VBAT by at least 45mV-indicating valid wall adapter presence. It includes a built-in 100ms filter to reject transient ringing. When VIN drops below this threshold, ACPR goes high-impedance. This signal enables system-level power-path control or LED indication without additional comparators, and is a core functional feature of the LTC4052EMS8E-4.2 for adapter-aware charging systems.

Does the LTC4052EMS8E-4.2 require an external blocking diode?

No-the LTC4052EMS8E-4.2 does not require an external blocking diode. Its internal N-MOSFET has the body tied to GND rather than the source, eliminating the parasitic body diode path from BAT to VIN. This architecture prevents reverse battery current flow if VIN is shorted to ground, a key differentiator from discrete-FET solutions. This feature is inherent to the LTC4052EMS8E-4.2 design and reduces both component count and forward-voltage losses.