NCP1010, NCP1011, NCP1012, NCP1013, NCP1014

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19

Typical Application Examples

A 6.5 W NCP1012−Based Flyback Converter

Figure 30 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:

Figure 30. An NCP1012−Based Flyback Converter Delivering 6.5 W

1

2

J1

CEE7.5/2

D1

D2

E1

10

m/400 V

E2

10

m/16 V

2

3

7

2

1

GND

GND

GND

HV

FB

GND

IC1

NCP1012

R2

150 k

D5

U160

5

4

4

8

C2

2n2/Y

4

8

7

6

5

TR1

1

E3

470

m/25 V

D6

B150

R3

100 R

R4

180 R

2

1

ZD1

11 V

J2

CZM5/2

IC2

PC817

C1

2.2 nF

1N4007

1N4007

R1

47 R

D3

D4

1N4007

1N4007

The converter built according to Figure 31 layouts, gave

the following results:

Figure 31. The NCP1012−Based PCB Layout . . . and its Associated Component Placement