Rev. F 05/18

13

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Figure 15. Typical LNK4214D and LNK4215D CP Output Characteristic Achieved.

VOUT (V)

IOUT (A)

100%

75%

100%

0

175% 200%

50%

33%

Low Mains

High Mains

VOUTCV(TYP)

IOUTCP(MIN)

IOUTCP(TYP)

IOUT(EXT)

Constant Power

The LNK4214D controller is optimized for fast start-up into loads with

large capacitance. The constant current (CC) pull-up set point of the

VI characteristic is determined by the value of R

CS. The controller

regulates in CC mode until it is above approximately 50% of the

programmed constant voltage (CV) regulation point (set by the values

of R

FB1 and RFB2). It then regulates in a power limited or “constant

power” (CP) mode until the output voltage reaches the CV set point,

at which point it changes to CV mode regulation. The exact trajectory

is dependent on the

input mains voltage.

I

OUT at the point of transition between CP and CV modes, IOUTCP, will be

greater than 57% of I

OUT(EXT) as shown in Figure 15.