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SLVS398D − JUNE 2001 − REVISED JULY 2003
PERFORMANCE GRAPHS
EFFICIENCY
vs
LOAD REGULATION
EFFICIENCY
vs
vs
OUTPUT CURRENT
OUTPUT CURRENT
OUTPUT CURRENT
1.004
1.003
100
95
90
85
80
75
70
65
60
55
50
100
V
V
T
= 5 V,
= 3.3 V,
= 25°C,
= 550 kHz
I
O
A
95
90
85
1.002
1.001
f
s
V
= 3.3 V
O
V
= 2.5 V
O
80
75
70
65
60
55
50
V
= 1.8 V
V
= 1.8 V
O
O
1
V
= 1.2 V
O
V
= 1.2 V
0.999
O
V
= 5 V,
V
= 3.3 V,
0.998
I
I
f = 550 kHz,
L = 4.7 µH,
f = 550 kHz,
L = 4.7 µH,
0.997
0.996
T
A
= 25°C
T
A
= 25°C
0
1
2
3
4
5
6
7
0
1
2
3
4
5
6
0
1
2
3
4
5
6
7
I
− Output Current − A
I
− Output Current − A
I
− Output Current − A
O
O
O
Figure 12
Figure 13
Figure 14
LINE REGULATION
vs
AMBIENT TEMPERATURE
vs
INPUT VOLTAGE
LOAD CURRENT
LOOP RESPONSE
1.002
125
115
105
95
60
180
135
V
V
T
= 5 V,
V
V
I
= 5 V,
I
I
T
J
= 125°C
= 3.3 V,
= 3.3 V,
1.0015
O
O
f
= 700 kHz
s
= 25°C,
= 550 kHz
= 6 A,
A
O
I
= 6 A
O
f
T
A
= 25°C,
1.001
1.0005
1
s
40
20
V
= 5 V
I
f
= 550 kHz
s
I
= 3 A
85
O
(1)
Safe Operating Area
75
90
65
Phase
V
= 3.3 V
0.9995
I
55
No Load
Gain
0
0.999
45
0
45
0.9985
0.998
35
−20
25
4
4.5
5
5.5
6
0
1
2
3
4
5
6
7
8
100
1 k
10 k
100 k
1 M
I
− Output Current − A
V − Input Voltage − V
I
O
f − Frequency − Hz
Figure 15
Figure 16
Figure 17
LOAD TRANSIENT RESPONSE
SLOW-START TIMING
OUTPUT RIPPLE VOLTAGE
V
= 5 V,
I
V
V
= 5 V,
I
0.047 µF
Slow-start Cap
= 3.3 V,
O
6A, 350 kHz
V
= 5 V,
I
1A to 5A,
4.0 ms/div
Time − 1 µs/div
100 µs/div
Figure 18
Figure 19
Figure 20
(1)
Safe operating area is applicable to the test board conditions in the Dissipation Ratings
10
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