SC5014 Datasheet, PDF (1/34 Pages) Semtech Corporation – High Efficiency 4-Channel HB LED Driver with I2C Interface and Phase-Shifted PWM Dimming

SC5014
POWER MANAGEMENT
Features
High Efficiency 4-Channel HB LED Driver with
I²C Interface and Phase-Shifted PWM Dimming
Description
 Input Voltage — 4.5V to 27V
 Output Voltage — Up to 50V
 Step-up (Boost) Controller
 Ultra-Fast Transient Response (<100μs)
 Programmable Switching Frequency
 Linear Current Sinks
 4 Strings, up to 120mA/String
 Current Matching ±1%
 Current Accuracy ±2%
 PWM Dimming
 String-by-String Phase Shifting
 Input Dimming Frequency 100Hz-30kHz
 User Selectable 9 or 10-Bits Dimming Resolution
 5-Bits Analog Dimming
 I²C Interface
 Fault Status — Open/Short LED, UVLO, OTP
 Device Control: PLL Setting
 Protection Features
 Open/Shorted LED(s) and adjustable OVP
 Over-Temperature and UVLO Shutdown Protection
 4mm X 4mm 20-pin QFN Package
Applications
 Ultrabooks^TM, All-in-One PCs, Monitors, Automotive-
Display Backlighting
 Backlighting for Mid-Size Displays
The SC5014 is a 4-channel, highly integrated, high-effi-
ciency step-up (boost) HB LED driver designed to reduce
the thickness of mid-size LCD displays. It features a wide
input voltage range (4.5V to 27V), phase-shifted PWM
dimming, analog dimming, a flexible output configura-
tion, an I²C interface, and numerous protection features.
The SC5014 exhibits 2% to 4% higher efficiency when
using the same size inductors as existing LED drivers. But,
unlike existing devices, it can also operate with inductors
that are up to 10x smaller without sacrificing efficiency.
This part can also use very low-profile inductors (as small
as 2.2µH, 1mm height), which allows LED drivers to be
built directly into the LCD panel to enable ultra-thin
displays.
The boost controller, with programmable switching fre-
quency from 200kHz to 2.2MHz, maximizes efficiency by
dynamically minimizing the output voltage while main-
taining LED string current accuracy. It provides excellent
line and load response with no external compensation
components. An external resistor adjusts the current from
20-120mA per string. It also features PWM dimming reso-
lution of 9 or 10-bits (user selectable) over a dimming fre-
quency from 100Hz to 20kHz, synchronized to the boost
oscillator. String-by-string phase shifting reduces the
demand on the input/output capacitance, decreases EMI,
and improves dimming linearity.
Typical Application Circuit
VIN=4.5 to 27V
VCC = 4.5 to 5.5V
R1
R2
FLT
EN
For I²C
PWMI
R3
C3
R6 R5
R10
R11
C4
R7
L1
UVLO
NDRV
CS
VCC
FLT ^SC5014
EN
SDA
SCL
PWMI
REF
OVP
IO1
IO2
IO3
SCP
FSET
ISET
CPLL
IO4
E-PAD
PGND
D1 VOUT up to 50V
Q1
R4
R9
C5
R8
Up to
120mA/String
Revision 2.0