Analog Devices Inc. LTC4088EDE-1#PBF

Overview

LTC4088EDE-1#PBF from Analog Devices (formerly Linear Technology) is a high-efficiency USB PowerPath™ controller and Li-Ion/Polymer battery charger in a 14-lead 4mm × 3mm × 0.75mm DFN package. It integrates a synchronous step-down switching regulator (2.25 MHz), ideal diode, NTC-based thermal management, and programmable input current limiting (100/500/1000 mA). It delivers regulated 3.6 V output during low-battery "instant-on" operation and supports media players, GPS devices, and smart phones requiring USB-powered charging with system load priority.

For engineers reviewing the LTC4088EDE-1#PBF datasheet, LTC4088EDE-1#PBF pinout, LTC4088EDE-1#PBF application, or LTC4088EDE-1#PBF equivalent, key selection considerations include its Bat-Track™ adaptive output control, 1.5 A max charge current with thermal limiting, 180 mΩ internal ideal diode on-resistance, and precise CLPROG-based input current regulation - all critical for USB-compliant portable power management designs.

Technical Context

The LTC4088EDE-1#PBF implements a precision average-input-current-limited buck converter with Bat-Track™ adaptive output control: VOUT tracks BAT + 0.3 V above 3.3 V, but regulates to a fixed 3.6 V when BAT < 3.3 V. Its dual-mode ideal diode (internal 180 mΩ PMOS + external GATE-driven P-channel) ensures seamless switchover from VBUS to BAT during input loss or overload.

Charge management uses constant-current/constant-voltage (CC/CV) with 4.2 V float voltage (±21 mV over –40°C to 85°C), programmable termination via C/X pin (1031× ratio), and safety timer (4.0 hours typical). Input current limit is set by D0/D1/D2 logic states and fine-tuned via CLPROG resistor (e.g., 2.94 kΩ yields 100 mA in 1x mode), with hCLPROG ratios of 224–2140 mA/mA enabling accurate USB compliance.

Key Specifications

Pinout & Package

Package: 14-lead (4 mm × 3 mm × 0.75 mm) plastic DFN with exposed pad (Pin 15 = GND, must be soldered).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar USB power management applications.

Compared with BQ24075RGTR and MAX1555ESA+, the LTC4088EDE-1#PBF uniquely combines Bat-Track™ adaptive output, integrated ideal diode, NTC-based thermal safety, and programmable multi-level USB current limiting - making it the only option supporting instant-on operation, USB-compliant high-power charging, and robust thermal management in a single 14-lead DFN.

Availability

LTC4088EDE-1#PBF is available at Aetrix Electronics and suitable for media players, GPS navigation devices, and smart phone accessories requiring stable component supply, USB-compliant power management, and single-cell Li-ion battery charging with thermal protection.

Supply support for LTC4088EDE-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) is a global leader in high-performance analog, mixed-signal, and power management ICs, serving industrial, automotive, communications, and consumer markets.

The LTC4088-1 product line was designed specifically for USB-powered portable electronics requiring intelligent power-path control, adaptive battery charging, and seamless backup power switchover - targeting space-constrained, thermally sensitive applications like handheld media and navigation devices.

FAQ

What is the default power-up behavior of the LTC4088EDE-1#PBF?

The LTC4088EDE-1#PBF powers up with the battery charger disabled (OFF state) when D0=D1=0 and D2=1. This differs from the LTC4088EDE-2#PBF, which powers up with charging enabled. The default OFF state prevents unintended battery charging during initial power application and allows system firmware to configure charge parameters before enabling the charger.

How does the LTC4088EDE-1#PBF maintain 3.6 V output during low-battery conditions?

The LTC4088EDE-1#PBF uses its Bat-Track™ circuitry to regulate VOUT to a fixed 3.6 V when BAT falls below 3.3 V, regardless of input current limit setting. This "instant-on" feature ensures system load operation immediately upon power application, even with deeply discharged batteries, by automatically reducing charge current to preserve minimum VOUT voltage.

Can the LTC4088EDE-1#PBF operate with a USB suspend source?

Yes, the LTC4088EDE-1#PBF includes a dedicated suspend LDO that activates when the main switching regulator is disabled. It provides 4.6 V at either 500 µA (low-power suspend) or 2.5 mA (high-power suspend), both compliant with USB 2.0 suspend specifications, preventing battery drain while connected to a suspended host.

What is the role of the CLPROG pin in the LTC4088EDE-1#PBF?

The CLPROG pin on the LTC4088EDE-1#PBF serves dual functions: it programs the average input current limit via a resistor to GND (e.g., 2.94 kΩ for 100 mA), and it monitors actual VBUS current through a precise hCLPROG ratio (224–2140 mA/mA). When CLPROG reaches 1.188 V, the switching regulator holds input current constant, ensuring strict USB compliance.

Does the LTC4088EDE-1#PBF support external temperature monitoring?

Yes, the LTC4088EDE-1#PBF supports external temperature monitoring via the NTC pin (Pin 1), which interfaces with a negative temperature coefficient thermistor co-packaged with the battery. It detects cold (75–78% VBUS) and hot (33–36% VBUS) thresholds and pauses charging outside the safe range, providing critical thermal protection for Li-ion batteries in portable devices.