Application Hints

INPUT CAPACITOR (C

To maintain stability, the regulator input pin must be by-

passed with at least a 100 µF electrolytic capacitor. The

capacitor’s leads must be kept short, and located near the

regulator.

If the operating temperature range includes temperatures

below −25˚C, the input capacitor value may need to be

larger. With most electrolytic capacitors, the capacitance

value decreases and the ESR increases with lower tempera-

tures and age. Paralleling a ceramic or solid tantalum ca-

pacitor will increase the regulator stability at cold tempera-

tures. For maximum capacitor operating lifetime, the

capacitor’s RMS ripple current rating should be greater than

V

R

Schottky

Fast Recovery

3A

4A–6A

3A

4A–6A

20V

1N5820

1N5823

The following

diodes are all

rated to 100V

31DF1

HER302

The following

diodes are all

rated to 100V

50WF10

MUR410

HER602

MBR320P

SR302

30V

1N5821

50WQ03

MBR330

1N5824

31DQ03

SR303

40V

1N5822

MBR340

MBR340

50WQ04

31DQ04

1N5825

SR304

50V

MBR350

50WQ05

31DQ05

SR305

60V

MBR360

50WR06

DQ06

50SQ060

SR306

FIGURE 8. Diode Selection Guide

Inductor

Inductor

Schott

Pulse Eng.

Renco

Code

Value

(Note 12)

(Note 13)

(Note 14)

L47

47 µH

671 26980

PE-53112

RL2442

L68

68 µH

671 26990

PE-92114

RL2443

L100

100 µH

671 27000

PE-92108

RL2444

L150

150 µH

671 27010

PE-53113

RL1954

L220

220 µH

671 27020

PE-52626

RL1953

L330

330 µH

671 27030

PE-52627

RL1952

L470

470 µH

671 27040

PE-53114

RL1951

L680

680 µH

671 27050

PE-52629

RL1950

H150

150 µH

671 27060

PE-53115

RL2445

H220

220 µH

671 27070

PE-53116

RL2446

H330

330 µH

671 27080

PE-53117

RL2447

H470

470 µH

671 27090

PE-53118

RL1961

H680

680 µH

671 27100

PE-53119

RL1960

H1000

1000 µH

671 27110

PE-53120

RL1959

H1500

1500 µH

671 27120

PE-53121

RL1958

H2200

2200 µH

671 27130

PE-53122

RL2448

Note 12: Schott Corporation, (612) 475-1173, 1000 Parkers Lake Road, Wayzata, MN 55391.

Note 13: Pulse Engineering, (619) 674-8100, P.O. Box 12235, San Diego, CA 92112.

Note 14: Renco Electronics Incorporated, (516) 586-5566, 60 Jeffryn Blvd. East, Deer Park, NY 11729.

FIGURE 9. Inductor Selection by Manufacturer’s Part Number

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