SM8120A
White LED Driver IC
OVERVIEW
The SM8120A is a high efficiency step-up DC/DC converter. Due to high voltage CMOS process realizing
24V output supply as maximum value, white LED of 2–4 lights connected in series can be lighted. By connect-
ing in series, current variation among LED is eliminated. Current value sent to white LED can be set by exter-
nal resistors. In addition, brightness can also be adjusted by control to FB pin or CE pin.
FEATURES
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PINOUT
(Top view)
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Boost-up control using PFM
White LED of 2-4 lights (connected in series)
lighted
Output current value can be set by external resis-
tors (51
Ω
: 9.8mA, 33
Ω
: 15.2mA, 24
Ω
: 20.8mA)
Brightness adjustable by control to FB pin or CE
pin
Current variation among LED decreased by high
precision
High efficient drive by step-up model
Supply voltage range: 2.4 to 5.5V
Maximum output voltage: 24V
Quiescent current: 80
µ
A (typ)
Standby current: 1.0
µ
A (max)
R
ON
(Switching MOS-Tr): 2
Ω
(typ)
Maximum switching frequency: 500kHz (typ)
Output current detection accuracy:
±
2%
Small package: SOT23-5
VDD
1
5
CE
VSS
2
SW
3
4
FB
PACKAGE DIMENSIONS
(Unit: mm)
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Cellular phone
Pager
Digital still camera
Handy terminal
PDAs
Portable games
White LED drive
LCD bias supply
Flash memory supply
+ 0.2
1.6
−
0.1
+ 0.2
2.8
−
0.3
1.9 ± 0.2
2.9 ± 0.2
0.4 ± 0.1
+ 0.1
0.15
−
0.05
0.12 M
1.1 ± 0.1
0 ~ 0.10
0.8 ± 0.1
0.95
0.1
ORDERING INFORMATION
Device
SM8120AH
Package
SOT23-5
NIPPON PRECISION CIRCUITS INC.—1
0.20MIN
APPLICATIONS