DER-285: 350mA @ 72V Max, 180 ~ 265VAC in

The document describes a non-isolated, power factor corrected, low THD, high-efficiency LED driver designed to drive a 72 V LED string at 350 mA from an input voltage range of 180 VAC to 265 VAC.

The LinkSwitch-PH has been developed to cost effectively design a highly efficient single-stage power factor corrected LED driver with primary-side constant current control. The LinkSwitch-PH controller was optimized for LED driver applications with minimal external parts count and control of the output current through the LED load without the use of an optocoupler.

The LinkSwitch-PH monolithically integrates the 725 V power MOSFET and controller. The controller consists of an oscillator, PWM, 6 V regulator, BYPASS (BP) pin programming functions, over-temperature protection, frequency jittering, cycle-by-cycle current limit, leading edge blanking, and charge controller for output CC (constant current) control.

The LinkSwitch-PH also provides a sophisticated range of protection features including auto-restart for control loop open/short faults and output short-circuit conditions. Accurate hysteretic thermal shutdown ensures safe average PCB temperatures under all conditions.

The non-isolated power factor corrected buck-boost presented in this report shows how LinkSwitch-PH dramatically simplifies off-line, high-efficiency, power factor corrected LED driver design with very low parts count.

This document contains the LED driver specification, schematic, PCB diagram, bill of materials, conducted EMI measurements, thermal measurements, inductor documentation and typical performance characteristics.