UCC2975_15 Datasheet, PDF (1/30 Pages) Texas Instruments – MULTI-TOPOLOGY PIEZOELECTRIC TRANSFORMER CONTROLLER

UCC2975, UCC2976, UCC2977
UCC3975, UCC3976, UCC3977
SLUS499A – NOVEMBER 2001 – REVISED JANUARY 2002
MULTIĆTOPOLOGY PIEZOELECTRIC
TRANSFORMER CONTROLLER
FEATURES
D 3-V to 13.5-V Operation
D Supports Flyback (UCC3975), Half-Bridge
(UCC3976), and Push-Pull (UCC3977)
Topologies
D Programmable Voltage Controlled Oscillator
D Open Lamp Protection
D Low Shutdown Current (15-µA Typical)
D Dual MOSFET Drivers
D 8-Pin TSSOP package
APPLICATIONS
D Notebook Computers
D Portable Electronics Displays
D Portable Instruments
SHUTDOWN
1 OPEN/SD
DESCRIPTION
Liquid crystal display (LCD) enclosures and cold
cathode fluorescent lamps (CCFLs) used in
notebook computer and portable electronics
displays are becoming increasingly narrow,
generating the need for a low profile CCFL power
supply. Recent advances in single- and
multi-layered piezoelectric ceramic transformers
(PZT) have enabled the development of a new
generation of efficient, size-reduced backlight
converters. The UCC3975/6/7 family of 8-pin PZT
controllers integrate the necessary circuitry for
operating a PZT-based backlight supply using a
flyback, half-bridge, or push-pull topology. The
choice of power topology depends on application
requirements such as input voltage, lamp voltage,
and PZT gain.
DOPEN
VDD 8
VDD
COPEN
ROPEN
ROSC
RCNT
COSC
2 OSC
OUTP 7
RANGE
UCC3976
CFB
3 COMP
4 FB
OUTN 6
GND 5
RFB _DFB
LRES
PIEZO
XFMR
RHV
RCS
CCFL
UDG–01092
Figure 1. UCC3976-Based CCFL Power Supply Using a Resonant Half-Bridge Topology
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
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Copyright  2002, Texas Instruments Incorporated
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