Only For Training And Service Purposes - LG GB220 Service Manual

The SC624 is a high efficiency charge pump LED driver using Semtech's proprietary mAhXLifeTM technology.
Performance is optimized for use in single-cell Li-ion battery applications.
The charge pump provides backlight current in conjunction with four matched current sinks. The load and
supply conditions determine whether the charge pump operates in 1x, 1.5x, or 2x mode. An optional fading
feature that gradually adjusts the backlight current is provided to simplify control software. The SC624 also
provides two low- dropout, low-noise linear regulators for powering a camera module or other peripheral
circuits.
The SC624 uses the proprietary SemWireTM single wire interface. The interface controls all functions of the
device, including backlight current and two LDO voltage outputs. The single wire implementation
minimizes microcontroller and interface pin counts.
In sleep mode, the device reduces quiescent current to 100μA while continuing to monitor the serial
interface. The two LDOs can be enabled when the device is in sleep mode. Total current reduces to
shutdown.
LGE Internal Use Only
Copyright © 2009 LG Electronics. Inc. All right reserved.

Only for training and service purposes

LCD CHARGEPUMP & CAM LDO
C324 1u
VBAT
C326 1u
C327
1u
1
C2-
2
U302
PGND
3
SC624ULTRT
NC1
4 EUSY0263105
MLED1 BL1
5
MLED2 BL2
MLED3
Figure 3-9-2. SC624 CIRCUIT DIAGRAM
C325
2.2u
15
LDO1
14
LDO2
13
BYP
12
NC3
11
SWIF
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
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3. TECHNICAL BRIEF
SWIF
0.1μA in
LGE Internal Use Only