SC600BIMLTR Semtech, SC600BIMLTR Datasheet - Page 11

• Manufacturer Part Number: SC600BIMLTR
• Description: IC, LED DRIVER, CHARGE PUMP, MLPD-10
• Manufacturer: Semtech

Specifications of SC600BIMLTR

• Led Driver Application: LED Backlighting, Portable Electronics
• No. Of Outputs: 1
• Output Current: 120mA
• Output Voltage: 4.725V
• Input Voltage: 2.5V To 6.5V
• Topology: Charge Pump
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Table 2 -Ripple Performance (Cont.)
Note: (1) SC600C is very similar to SC600B.
Mode Transition Impedance
The mode transition impedance Ro refers to the output
resistance of the charge pump before a transition to a
stronger mode occurs. Ro is dependent upon the frac-
tional charge pump, switching frequency, bucket capaci-
tor value, bucket capacitor ESR, and the internal switch
resistances.
Ro is proportional to,
Ro can be measured to verify a low transition imped-
ance. Before measuring Ro, select the capacitors, set
the operating frequency and a constant load current. Find
the input voltage just before a weak to strong mode tran-
sition (i.e., 1.5x to 2x mode). Measure V
before the transition.
Ro will be,
POWER MANAGEMENT
Applications Information (Cont.)
© 2006 Semtech Corp.
S
S
C
C
6
P
6
0
a
0
0
t r
0
B
D
N
(
) 1
. o
4
4
0 .
5 .
V
V
Ro=
F
e r
. q
2
6
6
2
6
6
3
3
mode V
8
6
5
5
8
6
5
5
2
2
k [
2
0
0
2
0
0
H
] z
I
OUT
IN
I
f C
O
1
U
T
1
1
1
1
1
1
V
4
4
1
1
2
2
2
2
2
2
[
0
0
OUT
0
0
m
0
0
0
0
0
0
] A
IN
O
, V
u
p t
OUT
t u
, and I
1
5 .
R
x
p i
2
3
1
2
4
3
3
2
1
1 1
1
0
0
4
m
p
0
0
0
5
5
5
0
5
0
e l
OUT
o
d
[
11
m
e
V
A lower value of Ro will improve efficiency, so low ESR
ceramic capacitors are required. An X7R or X5R dielec-
tric is recommended. Y5V dielectric can require 2 to 3
times the rated value of an X7R dielectric for the same
performance over the operating temperature range.
Efficiency
Efficiency for the SC600 is defined as,
- p
] p
O
η =
u
p
t u
V
2
R
IN
x
p i
m
5
9
2
2
4
5
4
2
2
4
p
5
5
0
0
0
5
5
0
0
0
mode I
o
e l
V
d
[
e
O
m
I
V
O
O
- p
] p
I
Q
C
O
0
0
U
T
3 .
3 .
1
1
1
1
1
1
1
1
μ [
3
3
] F
www.semtech.com
C
SC600
B
U
C
K
E
1
1
1
1
1
1
1
1
1
1
T
μ [
] F