SC4517A
POWER MANAGEMENT
Electrical Characteristics (Cont.)
Unless specified: V
IN
= 12V, V
COMP
= 0.8V, V
BST
= V
IN
+ 5V, EN = Tied to V
IN
, SYNC = 0, SW = open.
T
A
= T
J
= -40°C to 125°C.
PARAMETER
FB Input Current
Feedback Voltage
SYMBOL
I
FB
CONDITIONS
SC4517A (adj)
SC4517A (adj),
SC4517A-1.8V
3V < V
IN
< 16V
(1)
VOUT = VFB
SC4517A-2.5V
SC4517A-3.3V
SC4517A-5V
MIN
TYP
-0.25
MAX
-0.50
1.227
1.836
2.55
3.366
5.1
21.0
30.0
39.0
60.0
UNITS
µA
1.173
1.764
2.45
3.234
4.9
10.5
14.7
19.0
29.0
150
500
1.2
1.8
2.5
3.3
5
15.0
21.0
27.5
42.0
350
850
120
110
2.5
V
FB Input Resistance
R
FB
SC4517A-1.8V
SC4517A-2.5V
SC4517A-3.3V
SC4517A-5V
kΩ
FB to V
COMP
Voltage Gain
(2)
FB to V
COMP
Transconductance
(2)
V
COMP
Pin Source Current
V
COMP
Pin Sink Current
V
COMP
Pin to Switch Current
Transconductance
V
COMP
Pin Maximum Switching
Threshold
V
COMP
Pin Threshold
Maximum Switch Duty Cycle
Minimum Boost Voltage
Above Switch
Boost Current
0.4V
≤
V
COMP
≤
0.9V
∆
I
COMP
=
±
10µA
V
FB
= V
OUT(NOM)
- 17%
V
FB
= V
OUT(NOM)
+ 17%
1300
160
180
µMho
µA
µA
A/V
V
V
%
Duty cycle = 0%
I
SW
= 1.5A
V
COMP
= 1.2V, I
SW
= 400mA
I
SW
= 1.5A, 0°C
≤
T
A
≤
125°C and
I
SW
= 1.3A, T
A
< 0°C
I
SW
= 0.5A
I
SW
= 1.5A, 0°C
≤
T
A
≤
125°C and
I
SW
= 1.3A, T
A
< 0°C
80
0.35
0.9
90
1.8
10
30
2.7
15
45
V
mA
2006 Semtech Corp.
3
www.semtech.com
SEMTECH [ SEMTECH CORPORATION ]
