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All   >>  LED Lighting   >>   General Lighting Applications   >>   Questions
 

This is with respect to the Application note DN05047/D. It says in the circuit operation section that the output of the bridge rectifier is half sine wave, which incorrect. Also the circuit uses NSIC2030B ccr which is rated for 30 mA. Since the power rating of this design is 15 Watts, the LED current must be more than that ( around 5 0 mA). Kindly clarify.

The circuit in the application note uses a total of three CCRs in parallel—two 20 mA (NSIC2020B) and one 30 mA(NSIC2030B). One is switched on at a high voltage (CCR1 = 20 mA), and the other two are always on with the LEDs (CCR2 = 20mA, CCR3 = 30mA). So, whenever the LEDs are on, there is at least 50 mA of current, and at high voltages, there will be 70 mA. So you are correct in figuring the LED RMS current as roughly 50 mA—given there will be some off-time as well. Answered by:
ON Semiconductor
2013-07-16 23:59:15.57