MIC4574_05 Datasheet, PDF (6/7 Pages) Micrel Semiconductor – 200kHz Simple 0.5A Buck Regulator

MIC4574
Applications Information
The applications circuits that follow have been constructed
and tested. Refer to “Application Note 15” for additional
information, including efficiency graphs and manufacturer’s
addresses and telephone numbers for most circuits.
Micrel, Inc.
For a mathematical approach to component selection and
circuit design, refer to “Application Note 14.”
6V to 24V
C1
47µF
35V
3 _SHDN
SW ⁷
MIC4574-3.3BN
5 _VIN
FB ¹
SGND PGND
2
4
L1 _3.3V/0.5A
100µH
D1
1N5819
C2
220µF
16V
C1 Nichicon
C2 Nichicon
D1 Motorola
L1 Sumida
UPL1V470MEH, ESR = 0.34Ω
UPL1C221MPH, ESR = 0.16Ω
1N5819
RCH875-101K, DCR = 0.28Ω
Figure 1. 6V–24V to 3.3V/0.5A Buck Converter
Through Hole
8V to 24V
C1
47µF
35V
3 _SHDN
SW ⁷
MIC4574-5.0BN
5 _VIN
FB ¹
SGND PGND
2
4
L1 _5.0V/0.5A
100µH
D1
1N5819
C2
220µF
16V
C1 Nichicon
C2 Nichicon
D1 Motorola
L1 Sumida
UPL1J470MEH, ESR = 0.34Ω
UPL1C221MPH, ESR = 0.16Ω
1N5819
RCH875-101K, DCR = 0.28Ω
Figure 2. 8V–24V to 5V/0.5A Buck Converter
Through Hole
16V to 24V
C1
33µF
63V
3
SHDN
7
SW
MIC4574BN
5
1
V_IN
FB
SGND PGND
2
4
L1
220µH
MBR160
12V/0.5A
R2
13.0k
1%
R1
1.50k
1%
C2
220µF
16V
C1 Nichicon
C2 Nichicon
D1 Motorola
L1 Sumida
UPL1J330MEH, ESR = 0.35Ω
UPL1C221MPH, ESR = 0.16Ω
MBR160
RCH106-221K, DCR = 0.78Ω
Figure 3. 16V–24V to 12V/0.5A Buck Converter
Through Hole
M9999-062105
6
June 2005