Com pact LC D B ias Supply for TFT-LC D TV Panels
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FEATURES APPLICATIONS
• LCD TV Panel with ASG Technology
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• 8.5V to 14.7V Input Voltage Range• V
S
Output Voltage Range up to 19V
DESCRIPTION
• Boost Converter with 2.5A Switch Current
The TPS65171 offers a compact power supply
• Step Down Converter with 1A Switch Current
solution to provide all voltages required by a LCD
and Adjustable Output 2.5V to 3.3V
panel for large TV panel applications running from a
• 750kHz Fixed Switching Frequency
12V supply rail. The device is optimized to support
• Temperature Compensated Negative Supply
LCD technology using ASG gate drive circuits.
• High Voltage Stress Test (HVS)
The device generates all voltage rails for the TFTLCD bias (V
S
, V
ONE
, V
OFFE
, V
SS
). In addition to that it
• Adjustable Sequencing
includes a step-down converter (V
logic
) to provide the
• Gate Drive Signal for Isolation Switch
logic voltage. By pulling the HVS pin high an
• Short Circuit Protection
implemented high voltage stress test feature
• Internal Soft-Start
programs the boost converter output voltage V
s
tohigher values. The boost converter operates at a
• 180°Phase Shift Between Buck and Boost
fixed switching frequency of 750kHz. The positive
• P2P Short/Open Certified
charge pump is running from the boost converter and
• Optimized Dual Layer PCB Layout
is regulated by an external transistor. A buck-boostconverter provides an adjustable temperature
• Low EMI
dependent negative output voltage V
OFFE
. The
• Undervoltage Lockout
negative output voltage V
SS
is regulated by a shunt
• Thermal Shutdown
regulator.
• Available in 6×6mm 40 Pin QFN Package
Safety features like overvoltage protection of thebuck-boost input voltage, the boost and buck output
TYPICAL APPLICATION
voltage, undervoltage lockout, short circuit protectionof V
ONE
, V
OFFE
, and V
logic
are included as well asthermal shutdown.
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Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of TexasInstruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
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PowerPAD is a trademark of Texas Instruments.
PRODUCTION DATA information is current as of publication date.
Copyright © 2009–2010, Texas Instruments Incorporated
Products conform to specifications per the terms of the TexasInstruments standard warranty. Production processing does notnecessarily include testing of all parameters.