FAN2103_12 Datasheet, PDF (8/14 Pages) Fairchild Semiconductor – 3 A, 24 V Input, Integrated Synchronous Buck Regulator

Application Circuit
+5V
V_OUT
62
4.7n
1.0µ
X5R
VCC ₁₅
10K
PGOOD ₁₃
2.49K
2.49K
4.7n 56p
200K
NC ₂₄
COMP ₂₀
FB ₁₉
ILIM ₁₇
EN ₁₄
R(T) ₁₈
2.00K
30.1K
AGND ₁₆
4.7n
P2 ^VIN
200K
25 ^RAMP
8-20 V_IN
3.3n
2 x 4.7µ
X7R
1 ^BOOT
P1 ^SW
0.1µ
* TDK
RLF7030T-3R3M4R1
V_OUT
3.3µ *
1.5W
P3 ^PGND
390p
4 x 22µ
X5R
Figure 10. Application Circuit: 1.8 V_OUT, 500 KHz
Typical Performance Characteristics
Typical operating characteristics using the circuit shown in Figure 10. V_IN=16 V, V_CC=5 V, unless otherwise specified.
100
95
90
85
80
75
70
65
60
55
0.00
0.50
Efficiency
1.00
1.50
2.00
Load Current (A)
Effi12V (%)
Effi8V (%)
Effi18V (%)
2.50
3.00
Figure 11. 1.8 V_OUT Efficiency Over V_IN vs. Load
1.828
Regulation Characteristic
1.826
1.824
1.822
1.820
Vo8V (V)
Vo12V (V)
Vo18V (V)
1.818
0.00
0.50
1.00
1.50
2.00
2.50
3.00
Load Current (A)
Figure 13. 1.8 V_OUT Regulation vs. Load
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
0.00
Power Loss
Loss12V (W)
Loss8V (W)
Loss18V (W)
0.50
1.00
1.50
2.00
Load Current (A)
2.50
3.00
Figure 12. 1.8 V_OUT Dissipation Over V_IN vs. Load
Efficie ncy
100
95
90
85
80
75
70
65
0.00
0.50
V _IN=8V , 300KHz
V _IN=12V, 500Khz
1.00
1.50
2.00
Load Current (A)
2.50
3.00
Figure 14. 3.3 V_OUT Efficiency vs. Load
(Circuit Values Changed)
© 2007 Fairchild Semiconductor Corporation
FAN2103 • Rev. 1.0.8
8
www.fairchildsemi.com