LT1940LEFE#PBF

Overview

The LT1940LEFE#PBF is a dual current mode PWM step-down DC/DC converter manufactured by Analog Devices Inc. It features internal power switches rated for 2A, delivering an output current of 1.4A per channel. The device operates with a fixed switching frequency of 1.1MHz and accepts an input voltage range from 3.6V to 25V. It provides adjustable positive output voltages across two independent channels. The unit consumes 3.8mA of quiescent current and functions within a temperature range of -40°C to +85°C. It is housed in a 16-lead TSSOP package with an exposed pad (TSSOP-EP-16) for surface mount installation.

Feature Summary

• Dual monolithic architecture integrating two synchronized buck converters on a single chip
• Internal high-current power switches enable compact design without external pass elements
• Fixed 1.1MHz switching frequency allows for the use of small passive components
• Current mode control topology ensures fast transient response and loop stability

Applications

• Portable equipment requiring multiple regulated voltage rails
• Battery-powered systems needing efficient step-down conversion
• Industrial control boards utilizing distributed power architectures
• Communication infrastructure powering logic and analog circuits

Procurement Notes

Verify the specific suffix against official Analog Devices documentation to confirm package type and tape/reel specifications. Ensure compatibility with your PCB footprint, particularly the exposed thermal pad requirements for the TSSOP-EP-16 package. Cross-reference the manufacturer part number with authorized distributors to confirm authenticity and traceability. Check for any recent product change notices that may affect pinout or electrical characteristics.

Selection Notes

Select this component when a dual-channel solution is required to save board space compared to using two separate single-channel regulators. The 1.1MHz frequency is suitable for applications prioritizing component size over extreme efficiency at very low loads. Verify that the input voltage does not exceed the 25V maximum rating under all operating conditions. Consider the thermal performance of the TSSOP-EP-16 package relative to the expected load current and ambient temperature.

Part Context

This part belongs to the LT1940 series of dual synchronous buck converters. It shares the core architecture with variants such as the LT1940EFE#PBF, differing primarily in package configuration and manufacturing lot details. The series is designed for applications requiring two isolated or non-isolated regulated outputs from a single input source, offering a consolidated power management solution.

Replacement Considerations

LT1940EFE#PBF is a documented variant within the same family. Verify package dimensions and thermal pad connectivity before substitution.