Datasheet

LM1575, LM2575-N, LM2575HV
SNVS106E –MAY 1999–REVISED APRIL 2013 www.ti.com
PROCEDURE (Adjustable Output Voltage Versions) EXAMPLE (Adjustable Output Voltage Versions)
4. Catch Diode Selection (D1) 4. Catch Diode Selection (D1)
A. The catch-diode current rating must be at least 1.2 times greater A. For this example, a 3A current rating is adequate.
than the maximum load current. Also, if the power supply design
B. Use a 40V MBR340 or 31DQ04 Schottky diode, or any of the
must withstand a continuous output short, the diode should have a
suggested fast-recovery diodes in Table 1.
current rating equal to the maximum current limit of the LM2575. The
most stressful condition for this diode is an overload or shorted
output. See Table 1.
B. The reverse voltage rating of the diode should be at least 1.25
times the maximum input voltage.
5. Input Capacitor (C
IN
) 5. Input Capacitor (C
IN
)
An aluminum or tantalum electrolytic bypass capacitor located close A 100 μF aluminum electrolytic capacitor located near the input and
to the regulator is needed for stable operation. ground pins provides sufficient bypassing.
To further simplify the buck regulator design procedure, TI is making available computer design software to be
used with the Simple Switcher line of switching regulators. Switchers Made Simple (version 3.3) is available on
a (3½″) diskette for IBM compatible computers from a TI sales office in your area.
Table 1. Diode Selection Guide
Schottky Fast Recovery
V
R
1A 3A 1A 3A
20V 1N5817 1N5820
MBR120P MBR320
The following The following
SR102 SR302
diodes are all diodes are all
30V 1N5818 1N5821
MBR130P MBR330
rated to 100V: rated to 100V:
11DQ03 31DQ03
11DF1 31DF1
SR103 SR303
MUR110 MURD310
HER102 HER302
40V 1N5819 IN5822
MBR140P MBR340
11DQ04 31DQ04
SR104 SR304
50V MBR150 MBR350
11DQ05 31DQ05
SR105 SR305
60V MBR160 MBR360
11DQ06 31DQ06
SR106 SR306
Table 2. Inductor Selection by Manufacturer's Part Number
Inductor Code Inductor Value Schott
(1)
Pulse Eng.
(2)
Renco
(3)
L100 100 μH 67127000 PE-92108 RL2444
L150 150 μH 67127010 PE-53113 RL1954
L220 220 μH 67127020 PE-52626 RL1953
L330 330 μH 67127030 PE-52627 RL1952
L470 470 μH 67127040 PE-53114 RL1951
L680 680 μH 67127050 PE-52629 RL1950
H150 150 μH 67127060 PE-53115 RL2445
H220 220 μH 67127070 PE-53116 RL2446
H330 330 μH 67127080 PE-53117 RL2447
H470 470 μH 67127090 PE-53118 RL1961
H680 680 μH 67127100 PE-53119 RL1960
H1000 1000 μH 67127110 PE-53120 RL1959
(1) Schott Corp., [phone], 1000 Parkers Lake Rd., Wayzata, MN 55391.
(2) Pulse Engineering, [phone], P.O. Box 12236, San Diego, CA 92112.
(3) Renco Electronics Inc., [phone], 60 Jeffryn Blvd. East, Deer Park, NY 11729.
16 Submit Documentation Feedback Copyright © 1999–2013, Texas Instruments Incorporated
Product Folder Links: LM1575 LM2575-N LM2575HV