LT3975HMSE#PBF

Overview

The LT3975HMSE#PBF is a high-efficiency, adjustable-frequency monolithic buck switching regulator manufactured by Analog Devices Inc. It operates with an input voltage range of 4.2V to 42V and delivers up to 2.5A of load current. The device features a low quiescent current of 2.7µA in Burst Mode operation, ensuring high efficiency at light loads while maintaining output ripple below 15mV. It includes integrated Schottky diodes, current limit foldback for short-circuit protection, and maintains a low dropout voltage of 500mV during input transients such as automotive cold crank events.

Feature Summary

• Integrates internal synchronous rectification diodes to minimize external component count and board space.
• Utilizes Burst Mode operation to maintain high efficiency at low output currents while keeping output ripple extremely low.
• Provides current limit foldback functionality to restrict power dissipation during short-circuit conditions.
• Maintains stable regulation with low dropout voltage when input voltage drops below the programmed output level.

Applications

• Automotive systems requiring robust performance during cold crank events
• Industrial equipment needing wide input voltage tolerance
• Point-of-load conversion for microprocessors and FPGAs
• Battery-powered devices requiring extended runtime through low quiescent current

Procurement Notes

Verify the specific suffix 'HMSE' indicates the military/high-temperature grade variant when ordering. Confirm package type matches MSOP-10 requirements for your PCB layout. Ensure compatibility with LTspice simulation models if circuit design relies on manufacturer-provided tools. Check for RoHS compliance documentation if environmental regulations apply to your deployment.

Selection Notes

Select this component when a wide input voltage range up to 42V is required alongside high peak current capability. It is suitable for applications demanding minimal output ripple without external filtering complexity. Consider the MSOP-10 package constraints regarding thermal dissipation and pin pitch. Evaluate the need for adjustable frequency settings against fixed-frequency alternatives for noise-sensitive environments.

Part Context

This part belongs to the LT397x family of step-down regulators designed for high-efficiency power management. It shares architectural similarities with the LT3973 and LT3975 variants but offers specific current and thermal characteristics tailored for demanding industrial and automotive loads. The device integrates control logic and power switches into a single compact solution.

Replacement Considerations

• LT3975HMSE#TRPBF (Tape and Reel version of the same component)
• LT3975IUH#PBF (Commercial grade equivalent with different temperature range)

FAQ

What is the maximum input voltage supported by the LT3975HMSE#PBF?

The device supports a continuous input voltage range up to 42V.

How does the LT3975 handle short-circuit conditions?

It employs current limit foldback to reduce the output current and limit power dissipation during a short circuit.

Is an external catch diode required for the LT3975HMSE#PBF?

No, the device integrates internal synchronous rectification diodes, eliminating the need for an external catch diode.