NCP1070_16 Datasheet, PDF (22/30 Pages) ON Semiconductor – High-Voltage Switcher for Low Power Offline SMPS

NCP1070, NCP1071, NCP1072, NCP1075, NCP1076, NCP1077
Figure 36. Skip Cycle Schematic
Ramp Compensation and Ipk Set−point
In order to allow the NCP107X to operate in CCM with a
duty cycle above 50%, a fixed slope compensation is
internally applied to the current−mode control.
Here we got a table of the ramp compensation, the initial
current set point, and the final current set−point of different
versions of switcher.
NCP1070
NCP1071
NCP1072
NCP1075
NCP1076
NCP1077
Fsw
65 kHz
100 kHz
130 kHz
65 kHz
100 kHz
130 kHz
65 kHz
100 kHz
130 kHz
65 kHz
100 kHz
130 kHz
65 kHz
100 kHz
130 kHz
65 kHz
100 kHz
130 kHz
Sa
7 mA/ms
11 mA/ms
14 mA/ms
10 mA/ms
15 mA/ms
20 mA/ms
4.2 mA/ms
6.5 mA/ms
8.4 mA/ms
7.5 mA/ms
11.5 mA/ms
15 mA/ms
15 mA/ms
23 mA/ms
30 mA/ms
18 mA/ms
28 mA/ms
36 mA/ms
Ipk(Duty = 50%)
250 mA
350 mA
250 mA
450 mA
650 mA
800 mA
Ipk(0)
304 mA
425 mA
282 mA
508 mA
765 mA
940 mA
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