Only For Training And Service Purposes - LG GM210 Service Manual

3. TECHNICAL BRIEF
LCD_BL_CTRL
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 SemWire 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 0.1μA in shutdown.
LGE Internal Use Only
LGE Internal Use Only
2V8_LCD
1V5_CAM
FB101
15
LDO1
14
LDO2
13
BYP
12
NC3
11
SWIF
R115 C108
22n
100K
Figure 3-10-2 SC624 CIRCUIT DIAGRAM
VBAT
C103 C109
2.2u 2.2u
1
C2-
2
U100
PGND
3
SC624ULTRT
NC1
4
BL1
5
BL2
Copyright © 2008 LG Electronics. Inc. All right reserved.

Only for training and service purposes

- 42 - Copyright © 2009 LG Electronics. Inc. All right reserved.
FB100
MLED
C105
2.2u
LED_CA1
LED_CA3
LED_CA2
LED_CA4
Only for training and service purposes