Transformer Selection (T)

Figure 13 lists the standard transformers available for flyback regulator applications. Included in the table are the turns ratio(s) for

each transformer, as well as the output voltages, input voltage ranges, and the maximum load currents for each circuit.

Transformer Footprints

Figure 15 through 32 show the footprints of each transformer, listed in Figure 14.

Applications

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Transformers

T1

T1

T1

T2

T3

T4

V

IN

4V–6V

4V–6V

8V–16V

4V–6V

18V–36V

18V–36V

V

OUT1

3.3V

5V

12V

12V

12V

5V

I

1.8A

1.4A

1.2A

0.3A

1A

2.5A

N

1

1

1

1

2.5

0.8

0.35

V

OUT2

−12V

−12V

12V

I

0.3A

1A

0.5A

N

2

2.5

0.8

0.8

V

OUT3

−12V

I

0.5A

N

3

0.8

FIGURE 13. Transformer Selection Table

Transformer

Type

Manufacturers’ Part Numbers

Coilcraft

Coilcraft (Note 16)

Pulse (Note 17)

Renco

Schott

(Note 16)

Surface Mount

Surface Mount

(Note 18)

(Note 19)

T1

Q4434-B

Q4435-B

PE-68411

RL-5530

67141450

T2

Q4337-B

Q4436-B

PE-68412

RL-5531

67140860

T3

Q4343-B

—

PE-68421

RL-5534

67140920

T4

Q4344-B

—

PE-68422

RL-5535

67140930

Note 16: Coilcraft Inc.,:

Phone: (800) 322-2645

1102 Silver Lake Road, Cary, IL 60013:

Fax: (708) 639-1469

European Headquarters, 21 Napier Place:

Phone: +44 1236 730 595

Wardpark North, Cumbernauld, Scotland G68 0LL:

Fax: +44 1236 730 627

Note 17: Pulse Engineering Inc.,:

Phone: (619) 674-8100

12220 World Trade Drive, San Diego, CA 92128:

Fax: (619) 674-8262

European Headquarters, Dunmore Road:

Phone: +353 93 24 107

Tuam, Co. Galway, Ireland:

Fax: +353 93 24 459

Note 18: Renco Electronics Inc.,:

Phone: (800) 645-5828

60 Jeffryn Blvd. East, Deer Park, NY 11729:

Fax: (516) 586-5562

Note 19: Schott Corp.,:

Phone: (612) 475-1173

1000 Parkers Lane Road, Wayzata, MN 55391:

Fax: (612) 475-1786

FIGURE 14. Transformer Manufacturer Guide

T1

DS012420-31

Top View

FIGURE 15. Coilcraft Q4434-B

T2

DS012420-32

Top View

FIGURE 16. Coilcraft Q4337-B

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