Refer also to Section 6.2 Output capacitor and inductor selection for output capacitor design hints.

The dimming performance depends on the current pulse shape specification of the final application.

Figure 8. Dimming operation

DIM

t

T

LED

rise

t fall

T

DIM

I LED

The ideal current pulse has rectangular shape; however, in any case it degenerates into a trapezoid or, at worst,

into a triangle, depending on the ratio (tRISE + tFALL)/ TLED.

Figure 9. Dimming operation (rising edge) – VIN=44 V, 12 LED

ALED6000

Digital dimming

DS13018 - Rev 4

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