LT3750EMS#PBF

Specialized ICS Overview

The LT3750EMS#PBF is a flyback converter controller designed for rapidly charging large capacitors to user-adjustable target voltages. It utilizes a patented boundary mode control scheme to minimize transition losses and reduce transformer size. The device supports a wide input voltage range of 3V to 24V and features primary-side sensing, eliminating the need for output voltage divider resistors. A low 78mV current sense accurately limits peak switch current to maximize efficiency. Typical applications include charging a 100µF capacitor to 300V in less than 300ms. The controller drives high-current NMOS FETs with a gate voltage of VCC – 2V and provides a DONE pin to indicate when the target voltage is reached.

Specialized ICS Feature Summary

• Patented boundary mode control minimizes switching losses and reduces transformer size
• Primary-side sensing eliminates the need for high-voltage output voltage dividers
• Wide input voltage range from 3V to 24V accommodates various power sources
• 78mV precise current limit comparator ensures accurate peak switch current control

Specialized ICS Applications

• Emergency warning beacons
• Professional photoflash systems
• Security and inventory control systems
• High voltage power supplies
• Electric fences and detonators

Specialized ICS Procurement Notes

Verify the specific ordering suffix against the manufacturer's documentation to confirm package type and tape/reel configuration. The #PBF suffix indicates lead-free status. Confirm that the MSOP-10 package dimensions align with the PCB footprint requirements. Ensure the supply chain source provides valid traceability for Analog Devices Inc. components.

Specialized ICS Selection Notes

Select external components based on the required output voltage and charge current. The target voltage is set by the transformer turns ratio and external resistors RVOUT and RBG. Ensure the external NMOS drain-source voltage rating exceeds VTRANS plus the reflected output voltage. Choose an output diode with a reverse recovery time under 100ns to optimize charge efficiency and minimize leakage current effects.

Specialized ICS Part Context

The LT3750 is part of a family of specialized power management ICs focused on capacitor charging. Unlike general-purpose DC-DC controllers, it integrates specific logic for discontinuous mode detection and primary-side voltage monitoring. This specialization allows for simplified designs in high-voltage pulse applications where rapid energy transfer is critical.

Specialized ICS Replacement Considerations

LT3420/LT3420-1: 1.4A/1A photoflash charger with automatic top-off. LT3468/LT3468-1: 1.4A/1A/0.7A photoflash charger. LT3484-0/LT3484-1: 1.4A/0.7A/1A photoflash charger. LT3485-0/LT3485-1: 1.4A/0.7A/1A/2A photoflash charger with integrated IGBT driver.