MP4060—TRIAC Dimmable PFC, PSC LED Controller for 200-265VAC LEDs

MP4060 Rev. 1.0

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22

5/27/2015

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resistance of Ra.

Dimming Depth Enlargement

Driving a MOSFET to pull down a resistor from

the auxiliary winding to GND forms a dummy

load, which helps distribute the output current.

DIM working timing means a shorter the dimming

duty cycle

results in a higher dummy load

distribution current. This method enlarges the

dimming depth. The dimming depth enlargement

circuit is shown in Figure 20.

Figure 20—Dimming depth enlargement circuit