This kind of compensation network just provides one single low frequency pole, given by:

fPLF= 12π⋅CF⋅RU

(41)

Starting from Eq. (18) , the control loop gain module at s=2π*FBW allows fPLF necessary value to be set:

GLOOP,Is=2π⋅fBW = G0kFF⋅VIN⋅fPLFfBW=1

(42)

A typical choice for RU usually falls in the range 1 kΩ to 50 kΩ, in order to provide for CF a reasonable value (in

the range 1 nF – 100 nF) and to proper bias the overvoltage protection Zener diode.

ALED6000

Compensation strategy for alternative topologies

DS13018 - Rev 4

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