TPS61176
www.ti.com
SLVSBM5 –DECEMBER 2012
High-Efficiency 6-Channel WLED Driver Supporting Single-Cell Li-Ion Battery Input
Check for Samples: TPS61176
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FEATURES
DESCRIPTION
The TPS61176 is a highly integrated multi-channel
WLED backlight driver for tablet or notebook PCs,
which can support single-cell battery input directly. It
comprises a high efficient boost converter with an
integrated 2A/40V power MOSFET and six current
sink regulators. In total, the device can drive up to 60
WLEDs with high current matching performance. In
addition, the boost automatically adjusts its output
voltage to the WLED forward voltage to improve
efficiency.
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2.7V to 6.5V VIN Voltage Range
2.7V to 24V Boost Input Voltage Range
Integrated 2A/40V MOSFET
1MHz Switching Frequency
Adaptive Boost Output to WLED Voltages
Six Current Sinks of 35mA Capability Each
±2% (Max) Current Accuracy
1.3% (Typ) Current Matching
TPS61176 adopts mixed dimming mode. The
automatic switch between PWM dimming at low
dimming duty cycle and analog dimming at high
dimming duty cycle increases the overall electrical-to-
optical efficiency, reducing the power budget for
backlight remarkably. The switch point can be
programmed to 12.5% or 25% and the PWM dimming
mode can be programmed to fixed frequency
dimming or direct PWM dimming. TPS61176 supports
up to 14-bit dimming resolution, which avoids
potential flickering perception during the low
brightness dimming.
Wide PWM Dimming Frequency Range
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from 100Hz to 22kHz
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Mixed Dimming Mode: Automatic Switch
between Analog Dimming and PWM Dimming
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Programmable Switch Point: 25% / 12.5%
Programmable PWM Dimming Mode: 22kHz
PWM Dimming / Direct PWM Dimming
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Up to 14-bit Dimming Resolution
Support down to 1% Dimming Duty Cycle
Input PWM Glitch Filter
By providing a driver for an external isolation P-
channel MOSFET, TPS61176 can support true
shutdown. When the IC is disabled or the boost
output is short to ground, the isolation PFET can be
turned off to cut off the power path from battery to the
WLEDs, preventing any leakage current from the
battery. TPS61176 also integrates soft start, WLED
open and short protection and thermal shut down.
Up to 90% Efficiency
Driver for Input / Output Isolation PFET for
True Shutdown
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Built-in Soft Start
Built-in WLED Open / Short Protection
Thermal Shutdown
Support 4.7µH Inductor
TPS61176 is in a 16 pin 3mm x 3mm QFN package,
16L 3 mm x 3 mm QFN package
providing
a space-saving and high-performance
WLED driver solution.
APPLICATIONS
TYPICAL APPLICATION
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Tablet Backlight
L1
4.7uH
Notebook Backlight
2.7V ~ 6.5V
VIN
Up to 38V
D1
Backlight for Small and Media Form Factor
LCD Display with Single-Cell or Multi-Cell
Battery Input
C1
2.2uF
C2
4.7uF
SW
MODE / FAULT
VIN
R3
1M
R2
1.3M
PGND
OVP
R4
43k
TPS61176
IFB1
IFB2
IFB3
IFB4
VLDO
C3
1uF
IFB5
IFB6
PWM
PWM / EN
ISET
COMP
C4
0.47uF
R1
51k
GND
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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2012, Texas Instruments Incorporated