LTC4125EUFD#PBF

Updated: 2026-07-15

Overview

The LTC4125EUFD#PBF is a highly integrated wireless power receiver and battery charger IC developed by Linear Technology (now part of Analog Devices). It is designed to provide efficient power conversion from a wireless transmitter to charge single-cell lithium-ion/polymer batteries. This IC is particularly useful in applications where wired charging is impractical or undesirable, such as in industrial sensors, medical devices, and consumer electronics. The device operates at high efficiency to minimize power loss and heat generation during the charging process.

Structure and Working Principle

The LTC4125EUFD#PBF integrates a full-wave synchronous rectifier, a low-dropout linear charger, and a dynamic harmonization control system. The IC receives AC power from a wireless receiver coil and converts it to a regulated DC output for battery charging. The device employs a proprietary dynamic harmonization algorithm that optimizes power transfer efficiency regardless of coil alignment or distance variations. This makes it particularly robust in real-world applications where perfect alignment between transmitter and receiver cannot always be maintained.

Key Features

The LTC4125EUFD#PBF offers several notable features including programmable output voltage (up to 8V), output current limit (up to 400mA), and thermal regulation. The device operates with input frequencies from 110kHz to 205kHz, making it compatible with various wireless power standards. Additional features include battery temperature monitoring, charge termination based on battery voltage and current, and a power good output signal. The IC is packaged in a compact 4mm × 4mm QFN-20 package, making it suitable for space-constrained applications.

Application Areas

This IC is widely used in industrial applications such as wireless sensor networks, factory automation equipment, and medical devices where battery replacement is difficult. In consumer electronics, it finds use in smartphones, wearables, and IoT devices. The LTC4125EUFD#PBF is particularly valuable in applications requiring sealed enclosures or where waterproofing is essential, as it eliminates the need for physical charging ports. Its robust design makes it suitable for harsh environments where reliability is critical.

Maintenance and Precautions

When implementing the LTC4125EUFD#PBF, proper PCB layout is crucial to ensure optimal performance. High-frequency bypass capacitors should be placed as close as possible to the IC pins, and the ground plane should be continuous beneath the device. Thermal management is important, especially when operating at maximum output currents. The IC includes thermal regulation that reduces charge current if the die temperature becomes excessive, but adequate ventilation or heat sinking should still be considered in the design.

B2B Procurement Guide

When procuring the LTC4125EUFD#PBF, buyers should verify the authenticity of the parts as counterfeit ICs can be a concern in the electronics market. Purchasing from authorized distributors or directly from Analog Devices is recommended. For prototype quantities, consider purchasing through reputable electronics distributors. For production volumes, direct engagement with the manufacturer may yield better pricing and support. Lead times can vary, so early engagement in the design process is advisable.