AN1246

Key features of the VIPer20ADIP-E

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1

Key features of the VIPer20ADIP-E

2

General circuit description

flyback, working at 100 kHz. The output can deliver 12 V at 0.5 A continuous. This circuit

can be powered from the main bulk capacitors of an off-line power supply, power factor

correction output stage, or the AC line with the addition of a low current bridge rectifier. It

benefits from the EMI filter present in a typical power supply. The output uses a Schottky

diode for better efficiency. C7 is a low ESR capacitor which manages the ripple current. IC2

provides the reference and the feedback to tightly regulate the output. CS5, CS6, and RS3

form the feedback loop compensation to optimize stability during transients. The demoboard

can be tested with convection air. Depending on the final application, air flow might be

needed to keep the VIPer20ADIP-E under the thermal shutdown limit.

Figure 1.

Schematic

C12

220pF

1KV

CS6

.47u

RS5

1.37k

R6

150

R7

5.23k

RS10

nu

F1

0.5 A Pico Fuse

16T

C3

120uF

16V

c9

2.2n

Y cap

128T

C7

680uF

16V

J1

CON

1

2

CS4

3.9nF

DS2

STPS1H100A

RS4

1.6

D4

NU

14T

R11

2.7k

J2

CON

1

2

R9

3.9

RS14

82K

CS11

47n

R8

1.2k

CS5

33n

C10

220pF

1KV

IC2

TL431

R

DS3

LL4148

RS2

4.99K

C2

4.7uF

400V

L2

10uH

C8

330uF

16V

IC1

VIPer20ADIP-E

2

3

8

7

1

6

4

5

vdd

source

drain

drain

osc

drain

comp

drain

D1

BYT11-600

RS3

5.1k

Cramer Coil CSM 1608-027

T1

3

2

4

1

6

7

IC3

H11A817A