6 5 1:Switch 4 2:GND 3:Feedback Symbol Description 6:Supply SW Voltage GND 5:Over Voltage Symbol VIN OVP FB 4:Start-Up CE 1/8 Block Diagram LESHAN RADIO COMPANY, LTD. LR246 PIN4 PWM CONTROL Fosc PIN6(VIN) VREF SHUTDOWN CURRENT SENSE + SLOPE COMP + - gm PIN1(SW) PIN5(OVP) 00 0 PIN2(GND) .
LESHAN RADIO COMPANY, LTD. LR246 White LED Step-Up Converter LR246 is a step-up DC/DC converter specifically designed to drive white LED with a constant current. It can drive two,three,or four LEDS. It switches at 1.2MHz and use tiny external components. The output capacitor can be as small as 0.22uF,which can save space and cost versus alternative solutions. Feedback voltage is as low as 95mV. Built-in OverVoltage ¾ OverVoltage Function ¾ Fast 1.2MHz Switching Frequency ¾ Requires Only 0.22u.