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All   >>  LED Lighting   >>   LCD Backlighting Applications   >>   Questions
 

Hi, My earlier question was "We are using this device P/N: CAT4240TD-GT3 for one of LCD boost operation with 24V Vout. We need to understand how this device can used for 9.3V PWM out with 120 mA with Vin = 5V "..to add further..we are using PWM signal input to SHDN Pin to control PWM output for dimming appliction. VIN is at 5V. Are we able to get 9.3V @ 120 mA if we get the value of Rs = 2.5Ohm and L= 26 uH..please confirm..

Yes, as I have explained in previous post.LED brightness dimming can be done by applying a PWM signal to the SHDN input. The LED current is repetitively turned on and off, so that the average current is proportional to the duty cycle. A 100% duty cycle, with SHDN always high, corresponds to the LEDs at nominal current. The recommended PWM frequency range is from 100 Hz to 2 kHz and the maximum voltage on SHDN pin is 7V. Answered by:
ON Semiconductor
2013-01-23 14:42:38.946