© 2011 Semtech Corporation
POWER MANAGEMENT
1
SC5010
High E ciency 8-Channel LED Driver with
I
2
C Interface and Phase-Shifted PWM Dimming
Features
VIN Range — 4.5V to 27V, VOUT Range — Up to 50V
Step-up (Boost) Controller
Excellent Transient Response
Programmable Switching Frequency
Linear Current Sinks
8 Strings, up to 30mA/String
Current Matching ±1%
Current Accuracy ±1.5%
PWM Dimming
String-by-String Phase Shifting
Input Dimming Frequency 100Hz-30kHz
User Selectable 9 or 10 Bits Dimming Resolution
Optional Synchronization to VSYNC/HSYNC
Signal
5-bit Analog Dimming
Optional External p-MOSFET Disconnect Switch
True Load Disconnect and Inrush Current Limiting
I
2
C Interface
Fault Status — Open/Short LED, UVLO, OTP
Device Control — SYNC Freq, PLL Setting
Protection Features
Open/Shorted LED(s) and adjustable OVP
Over-Temperature and UVLO Shutdown Protection
4 X 4(mm) 28-pin QFN Package
Applications
Notebook PCs, UMPC, LCD Monitors, and Tablet PCs
Description
The SC5010 is an 8-channel high-precision, high-e ciency
step-up (Boost) LED driver for backlight applications. It fea-
tures wide input voltage range (4.5V to 27V) , exible output
configuration, wide analog and PWM dimming range,
phase shifting and fading. It also features video signal syn-
chronization (VSYNC), I
2
C interface, and numerous protec-
tion features. An optional disconnect p-MOSFET provides
true load disconnection and inrush current limiting.
The boost controller, with programmable switching fre-
quency from 200kHz to 2.2MHz, maximizes e ciency by
dynamically minimizing the output voltage while maintain-
ing LED string current accuracy. It provides excellent line
and load response with no external compensation compo-
nents. Each linear current sink is matched within ±1% for
superb lighting uniformity, and the accuracy of each string
current is ±1.5%. An external resistor adjusts the current
from 10-30mA per string. It also features PWM dimming
resolution of 9 or 10 bits (user selectable) over dimming
frequency from 100Hz to 20kHz, synchronized to the SYNC
signal or the boost oscillator. String-by-string phase shifting
reduces the demand on the input/output capacitance,
decreases EMI, and improves dimming linearity.
SC5010 is available in a low-pro le, thermally enhanced,
4 X 4 X 0.6(mm) QFN 28-pin package.
UVLO
AGND
ISET
FSET
CPLL
SCP
DRVP
VIN
SC5010
R3
R6
FLT
C3
BG
FLT
VCC
PGND
R11
R7
C4
R10
R1
R2
C1
Q2
C2
OVP
IO8
IO1
R9
R8
V
IN
=4.5 to 27V
Up to
30mA/CH
IO2
IO3
IO4
IO5
IO6
C5
IO7
R5
PWMI
PWMI
SYNC
SYNC
SDA
SCL
For I
2
C
EN
EN
L1
Q1
R4
DRVN
CS
D1
V
OUT
up to 50V
V
CC
= 4.5 to 5.5V
(Optional)
2.2μH
4.7μF
Typical Application Circuit
Revision 1.0
