Datasheet

Typical Application Circuits
This section provides several application solutions with a bill
of materials. All bill of materials reference the below figure.
The compensation for these solutions were optimized to work
over a wide range of input and output voltages; if a faster
transient response is needed reduce the value of C
C1
and
calculate the new value for R
C1
as outline in the design guide.
30030801
FIGURE 11.
Bill of Materials (V
IN
= 5V, V
OUT
= 3.3V, I
OUTMAX
= 4A)
Designator Description Part Number Manufacturer Qty
U1 Synchronous Buck Regulator LM20154 National Semiconductor 1
C
IN
100 µF, 1210, X5R, 6.3V GRM32ER60J107ME20 Murata 1
C
OUT
100 µF, 1210, X5R, 6.3V GRM32ER60J107ME20 Murata 1
L
1 µH, 6 mΩ
MSS1038-102NL Vishay 1
R
F
1Ω, 0603
CRCW06031R0J-e3 Vishay-Dale 1
C
F
100 nF, 0603, X7R, 16V GRM188R71C104KA01 Murata 1
C
VCC
1 µF, 0603, X5R, 6.3V GRM188R60J105KA01 Murata 1
R
C1
7.87 kΩ, 0603
CRCW06037871F-e3 Vishay-Dale 1
C
C1
2.2 nF, 0603, X7R, 25V VJ0603Y242KXXA Vishay-Vitramon 1
C
SS
33 nF, 0603, X7R, 25V VJ0603Y333KXXA Vishay-Vitramon 1
R
FB1
31.6 kΩ, 0603
CRCW06033162F-e3 Vishay-Dale 1
R
FB2
10.2 kΩ, 0603
CRCW06031022F-e3 Vishay-Dale 1
R
S
3.24 kΩ, 0603
CRCW06033241F-e3 Vishay-Dale 1
Bill of Materials (V
IN
= 3.3V to 5V, V
OUT
= 1.2V, I
OUTMAX
= 4A)
Designator Description Part Number Manufacturer Qty
U1 Synchronous Buck Regulator LM20154 National Semiconductor 1
C
IN
100 µF, 1210, X5R, 6.3V GRM32ER60J107ME20 Murata 1
C
OUT
100 µF, 1210, X5R, 6.3V GRM32ER60J107ME20 Murata 1
L
1 µH, 6 mΩ
MSS1038-102NL Coilcraft 1
R
F
1Ω, 0603
CRCW06031R0J-e3 Vishay-Dale 1
C
F
100 nF, 0603, X7R, 16V GRM188R71C104KA01 Murata 1
C
VCC
1 µF, 0603, X5R, 6.3V GRM188R60J105KA01 Murata 1
R
C1
3.57 kΩ, 0603
CRCW06033571F-e3 Vishay-Dale 1
C
C1
3.3 nF, 0603, X7R, 25V VJ0603Y332KXXA Vishay-Vitramon 1
C
SS
33 nF, 0603, X7R, 25V VJ0603Y333KXXA Vishay-Vitramon 1
R
FB1
4.99 kΩ, 0603
CRCW06034991F-e3 Vishay-Dale 1
R
FB2
10 kΩ, 0603
CRCW06031002F-e3 Vishay-Dale 1
R
S
3.24 kΩ, 0603
CRCW06033241F-e3 Vishay-Dale 1
19 www.national.com
LM20154