LT3762 60V Synchronous Boost LED Controller

Product Details

The LT3762 is a synchronous DC/DC controller designed to operate as a constant-current source and constant-voltage regulator. It features a programmable internal PWM dimming signal generator and a synchronous gate driver. The LT3762 is ideally suited for driving high current LEDs with high efficiency and reduced power loss. Rail-to-rail switch current sensing enables synchronous boost topologies and nonsynchronous topologies such as SEPIC. A voltage feedback pin serves as the input for several LED protection features and also allows the converter to operate as a constant-voltage source.

A frequency adjust pin allows the user to program the frequency from 100kHz to 1MHz to optimize efficiency, performance and external component size. Adding a capacitor at SSFM pin activates the Spread-Spectrum Modulation feature to reduce EMI. The LT3762 also includes an integrated DC/DC converter to efficiently produce a regulated 7.5V supply for the N-channel MOSFET gate drivers. The PWM pin controls PWMTG to drive the P-channel MOSFET, allowing a high PWM dimming range (3000:1) and providing LED overcurrent protection and short-circuit protected boost capability.

Applications

  • Industrial and Automotive Lighting
  • Accurate Current-Limited Voltage Regulators


Features and Benefits

  • 3000:1 External PWM Dimming
  • 250:1 Internal PWM Dimming
  • Wide VIN Operating Range: 2.5V to 38.5V
  • Synchronous Boost Output Voltage up to 60V
  • Spread-Spectrum Frequency Modulation for Lower EMI
  • PMOS Switch Driver for PWM and Output Disconnect
  • Constant Current (±3.5%) Regulation
  • Constant Voltage (±2%) Regulation
  • Rail-to-Rail LED Current Sense: 0V to 60V
  • Programmable VIN Undervoltage Lockout
  • Analog Dimming via Two Control Pins
  • 100kHz to 1MHz Operation
  • Programmable Open LED Protection with OPENLED Flag
  • Short-Circuit Protection and SHORTLED Flag
  • Drives LEDs in Boost, SEPIC, Buck Mode, or BuckBoost Mode Configurations
  • 28 Lead TSSOP and QFN (4mm × 5mm) Exposed Pad Packages