NCP1010_14 Datasheet, PDF (19/23 Pages) ON Semiconductor – Self-Supplied Monolithic Switcher for Low Standby-Power Offline SMPS

NCP1010, NCP1011, NCP1012, NCP1013, NCP1014
Typical Application Examples
A 6.5 W NCP1012−Based Flyback Converter
Figure 28 shows a converter built with a NCP1012
delivering 6.5 W from a universal input. The board uses the
Dynamic Self−Supply and a simplified Zener−type
feedback. This configuration was selected for cost reasons
and a more precise circuitry can be used, e.g. based on a
TL431:
R1
47 R
1
2
J1
CEE7.5/2
D1
1N4007
D2
1N4007
E1
10 m/400 V
D3
1N4007
D4
1N4007
E2
10 m/16 V
R2
150 k
C1
2.2 nF
D5
U160
IC1
NCP1012
1
V_CC
HV ⁵
2
3
7
GND
GND
GND
FB ⁴
8
GND
1 ^TR1 8
7
6
4
5
IC2
PC817
D6
B150
E3
470 m/25 V
ZD1
11 V
R3
100 R
2
1
J2
CZM5/2
R4
180 R
C2
2n2/Y
Figure 28. An NCP1012−Based Flyback Converter Delivering 6.5 W
The converter built according to Figure 29 layouts, gave
the following results:
• Efficiency at Vin = 100 Vac and Pout = 6.5 W = 75.7%
• Efficiency at Vin = 230 Vac and Pout = 6.5 W = 76.5%
Figure 29. The NCP1012−Based PCB Layout . . . and its Associated Component Placement
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