LT3840IFE

Overview

The LT3840IFE is a high-voltage synchronous step-down switching regulator controller from Analog Devices Inc., designed for wide input voltage ranges between 2.5V and 60V. It supports buck, inverting, and boost topologies with output voltages adjustable from 1.25V to 60V. The device features a low quiescent current of 6µA and operates at a fixed switching frequency of 1MHz. It delivers up to 20A output current through integrated gate drivers powered by an internal buck-boost supply. The component functions within a temperature range of -40°C to +125°C and is housed in a 38-lead QFN package.

Feature Summary

• Integrated buck-boost supply enables efficient gate drive for high-side MOSFETs without external bootstrap components
• Accurate current limit protection ensures reliable operation under overload conditions
• Low quiescent current minimizes power consumption during standby or light-load operations

Applications

• Industrial power supplies requiring wide input voltage tolerance
• Automotive electronics systems operating across varying battery voltages
• Telecommunications infrastructure equipment needing stable DC-DC conversion

Procurement Notes

Verify the exact suffix (e.g., #PBF) against manufacturer specifications to ensure compliance with RoHS directives and lead-free requirements. Confirm package type matches design constraints, as variants exist in different footprints. Cross-reference ordering information with official Analog Devices documentation to avoid discrepancies in pinout or thermal performance characteristics.

Selection Notes

Select this controller when designing systems requiring high input voltage capability up to 60V with precise current limiting. Consider the 1MHz switching frequency for balancing efficiency and component size. Ensure thermal management aligns with the QFN package's heat dissipation capabilities. Validate compatibility with external MOSFETs regarding gate drive voltage levels provided by the internal supply.

Part Context

The LT3840 belongs to Analog Devices' family of high-voltage synchronous regulators. It complements other controllers like the LT3840IFE#PBF, which shares similar electrical characteristics but may differ in packaging or environmental ratings. This series targets applications demanding robust performance in harsh environments with strict power management needs.

Replacement Considerations

Direct substitutes include LT3840IUFE#PBF, offering identical functionality in alternative packaging. Verify pin compatibility and thermal resistance values before substitution. Consult Analog Devices documentation for any minor differences in recommended operating conditions or application circuit recommendations.