sc483itstrt Semtech Corporation, sc483itstrt Datasheet - Page 4

• Manufacturer Part Number: sc483itstrt
• Description: Sc483 Dual Synchronous Buck Pseudo-fixed-frequency Power-supply Controller
• Manufacturer: Semtech Corporation

Test Conditions: V
Notes:
(1) When the inductor is in continuous and discontinuous conduction mode, the output voltage will have a DC
regulation level higher than the error-comparator threshold by 50% of the ripple voltage.
(2) Using a current sense resistor, this measurement relates to PGND minus the voltage of the source on the low-
side MOSFET. These values guaranteed by the ILIM Source Current and Current Comparator Offset tests.
(3) clks = Switching cycles.
(4) Guaranteed by design. See Shoot-Through Delay Timing Diagram on Page 6.
(5) Semtech’s SmartDriver
At this point, an additional pullup device is activated, reducing the resistance to 2 (typ.). This negates the need for
an external gate or boost resistor.
POWER MANAGEMENT
Electrical Characteristics (Cont.)
P
F
P
V
O
n I
L
L
L
E
S
S
U
G
S
D
D
D
D
D
D
D
2005 Semtech Corp.
o
o
o
a
a
G
C
N
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o
n
h
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a
L
L
L
L
H
H
H
p
g
g
g
u
r e
d
o
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t f
t f
e t
P /
D
C
u
P
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P
S
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c i
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r e
t o
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P
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t l
s t
m
A
S
l l u
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S
l l u
l l u
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D
k n
T -
P
V -
k n
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n I
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D -
U -
r
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U -
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c r
p
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t u
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e r
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d l
FET drive first pulls DH high with a pullup resistance of 10 (typ.) until LX = 1.5V (typ.).
1
C
F
F
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E
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R
R
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D
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° 0
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=
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A
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3
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° 5
3
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4
4
5
6
2
2
2
OUT1
0 .
0 .
8 .
5 .
0 .
1 .
3 .
3 .
0
p
0
0
5
C
= V
OUT2
M
=1.25V, R
a
x
4 -
TON1
M
3
3
° 0
7 .
1 .
n i
C
= R
o t
TON2
1
www.semtech.com
M
= 1M
2
4
1
1
° 5
4
4
4
a
3 .
2 .
6 .
SC483
x
C
U
l c
l c
M
°C
µ
s k
s k
i n
s n
V
V
V
V
A
A
A
s
s t
(
(
) 3
) 3