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RD0802

setting before shutting down when power is switched off, therefore allowing the ballast

start up at that same setting when power is restored, no matter how long the ballast has

reference design kit. There are of course several alternative low cost micro controllers that

could be used equally well to realize this kind of ballast and that contain the same

functionality.

Figure 4.1 shows the microcontroller PWM outputs for all 4 dimming level.

Maximum Dim Level

Intermediate Dim Level 1

Intermediate Dim Level 2

Minimum Dim Level

Figure 4.1: Microcontroller PWM Outputs