TPS68000 Datasheet, PDF (1/13 Pages) Texas Instruments – HIGHLY EFFICIENT PHASE SHIFT FULL BRIDGE CCFL CONTROLLER

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(6,4 mm x 7,8 mm)
TPS68000
SLVS524 – OCTOBER 2005
HIGHLY EFFICIENT PHASE SHIFT FULL BRIDGE CCFL CONTROLLER
FEATURES
• 8-V to 30-V Input Voltage Range
• Full Bridge Topology With Integrated Gate
Drives for 4 NMOS Switches
• Synchronizable Constant Frequency
Operation
• Programmabe Phase Delays of Operating
Frequency for Master-Slave Operation
• Lamp Voltage and Lamp Current Regulation
• Analog and Burst Dimming
• Configurable Distributed Burst Dimming in
Multiple Controller Applications
• Programmable Voltage Regulation Timeout
for Startup and Fault Conditions
• Open-Lamp and Short-Circuit Protection
• Internal Over-Temperature Protection
• Undervoltage Lockout
• 30-pin TSSOP Package
APPLICATIONS
• CCFL Backlight Power Supplies for Desktop
Monitors and LCD TVs
• CCFL Backlight Power Supplies for Notebook
Computers
DESCRIPTION
The TPS68000 device provides a power supply
controller solution for CCFL backlight applications in a
large variety of applications. The wide input voltage
range of 8 V to 30 V makes it suitable to be powered
directly from regulated 12-V or 24-V rails, or any
other source with output voltages in this range. When
using a regulated 5-V rail, it also can be used in
notebook computers or other portable
battery-powered equipment having lower minimum
supply voltages. The controller is capable of driving
the gates of all 4 NMOS switches directly without the
need for any additional circuitry, like dedicated gate
drivers or gate-drive transformers. The wide input
voltage range also makes it easy to design CCFL
converters with higher input voltages like 120 V or
400 V coming from a power factor correction unit.
The TPS68000 also supports CCFL converter circuits
driving multi-lamp applications, either by using higher
power-rated switches and transformers, or using
several TPS68000s synchronized. When
synchronized, they can be operated either at the
same frequency and phase, or phase shifted to
minimize RMS input current. Already implemented
smart dimming features, such as support of
distributed dimming, also help to optimize the
performance of multi-controller applications.
(Continued on next page)
Supply Voltage
8V .. 30V
C₁
Error Output
Synchronization
Synchronization Phase Shift 0 V
Operating Frequency
Device Enable
Lamp current
(Analog Dimming Input)
0V
Burst Duty Cycle
0V
(Burst Dimming Input)
Burst Frequency
Direct Burst Dimming Input
(Frequency + Duty Cycle)
C₁₀
TPS68000
VCC
VLOGIC
R₂
2.0 V
R₁
C₅
FAULT
SYNC
PH
SET
EN
STC
3.3 V
2V
C₆
ABR
BBR
BF
BC
C₇
VREF
GND
V5A
Q_A
GA
SA
C₃
V5C
GC ^{C 4}
SC
GB
GD
V5
Q_B
C₂
OCP
CSEN
CAO
C₈
CA−
VSEN
VAO
C₉
VA−
PGND
Q_C
C₁₄
C₁₂
T₁
Q_D
C₁₃
R₃ ^R4
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCT PREVIEW information concerns products in the
formative or design phase of development. Characteristic data and
other specifications are design goals. Texas Instruments reserves
the right to change or discontinue these products without notice.
Copyright © 2005, Texas Instruments Incorporated