NCP1212 ON Semiconductor, NCP1212 Datasheet - Page 19

• Manufacturer Part Number: NCP1212
• Description: Current Mode Pwm Controller For Both Forward And Flyback Converters
• Manufacturer: ON Semiconductor

Channel 2 is the CS input pin waveform.
1
2
The skip mode operation waveform at light load is shown in Figure 44. Where Channel 1 is the gate drive pin waveform and
0.1
3
PNP
Q1
4
3 K
R2
100
VCC
Q2
PNP
R8
2.5 K
CS
FB
Figure 43. Suggested Solution for Better Light Load Regulation
9 K
Figure 44. Skip Mode Switching Waveform at Light Load
+5 V
3 R
+
−
300 ns
1 V
LEB
R
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Block
OSC
NCP1212
Output
Output
19
+
+
−
−
Current
Limit
Reset
Set
2
3
4
1
R
S
F/F
Q
Q
Totem Pole
Driver
Output