AN1439

Design specification

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1

Design specification

Table 1 summarizes the electrical specifications of the application, Table 2 provides the

BOM and Table 3 lists the transformer's specifications. The electrical schematic is shown in

Figure 1 and the PCB layout in Figure 2.

Figure 1.

STEVAL-ISC001V1 evaluation board: electrical schematic

The electrical specification is typical of an AC-DC adapter for consumer equipment, usually

developed as an external unit. As such, it falls within the scope of the European "Code of

Conduct on Efficiency of External Power Supplies" and is required to be "efficient" under no-

load conditions as specified in Table 4. The design target is to fulfill the phase 2

requirements, so as to be up-to-date until the year 2005, when phase 3 sets even more

stringent limits. Some hints to upgrade the design according to phase 3 is given in the

section Evaluation board optimization for minimum no-load consumption on page 13.

Table 1.

STEVAL-ISC001V1 evaluation board: electrical specifications

50/60 Hz

30 W

Output

60 kHz

η> 80%

Maximum no-load input power

1.

Compliant with European Code of Conduct on Efficiency of External Power Supplies, phase 2, 01.01.2003.

8

3

R2

1.5M

B1 DF06G

R3

1.5M

R4

18K

C5

100 F

400V

D1

1N4148

D2

1N4148

R16

220K

R10

1.5

R9

1.5

C14

47nF

400V

D4

1.5KE220A

Q1

STP5NK80ZFP

D3

STTH1L06

F1 2A fuse

NTC1 10R

R1 100

Vin

88V to

264Vac

D5 1N4148

R5 4.7

R8 47K

R6 220

R7 10

R12 33K

IC2

TL431

D6 1N4148

T1

1

3

6

IC1

L6565

1

2

7

5

2

2

3

3

4

1

1

C6 2.2nF Y1

D7

STPS8H100FP

L2

10 H

R15

5.6K

C7

47 F

25V

C10,C11

680F

25V

R14

2K

R13

10K

15V

2A

D01IN1303B

IC3 PC817X1

R11

1.5K

C8

1nF

C9

2.2nF

C15

100pF

1kV

C7b

100nF

C13

560nF

4

8

5

4

10

C12

330F

25V