NCP3065D3SLDGEVB(2): 350mA @ 7 ~ 23V out, 8 ~ 25V in

* The eval board must be modified for 350mA output. The Transformer/Dual inductor and sense resistor(s).

This circuit is intended for driving high power LEDs, such as the Cree XLAMP™ series, Lumileds Luxeon™ Rebel and K2 and OSRAM, Golden and Platinum Dragon™ as well as the OSTAR™. It is designed for such wide input nominal 12 Vdc applications as automotive and low voltage lighting (12 Vdc/12 Vac). An optional dimming PWM input is included.

The circuit is based on NCP3065 operation at 250 kHz in a non-isolated configuration. The primary advantages of this circuit are in the wide input voltage range, wide output voltage range, and in its high efficiency.

A pulse feedback resistor (R8) is used to vary the slope of the oscillator ramp, achieving duty cycle control and steady switching frequency over a wide input voltage range.