LT1768CGN Linear Technology, LT1768CGN Datasheet - Page 15

• Manufacturer Part Number: LT1768CGN
• Description: IC CTRLR CCFL SGL/MULT HP 16SSOP
• Manufacturer: Linear Technology
• Type: CCFL Controllerr

Specifications of LT1768CGN

• Frequency: 300 ~ 410 kHz
• Current - Supply: 7mA
• Current - Output: 1.5A
• Voltage - Supply: 9 V ~ 24 V
• Operating Temperature: 0°C ~ 125°C
• Package / Case: 16-SSOP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

APPLICATIONS
Supply Bypass and Layout Considerations
Proper supply bypassing and layout techniques must be
used to insure proper regulation, avoid display flicker, and
insure long term reliability.
Figure 8 shows the application’s critical high current paths
in thick lines. Ideally, all components in the high current
path should be placed as close as possible and connected
with short thick traces. The most critical consideration is
that T1’s center tap, the Schottky diode D1, LT1768’s V
pin, and a low ESR capacitor (C1) be connected directly
*OPTIONAL
BOLD LINES INDICATE
HIGH CURRENT PATHS
V IN
C2
C1
U
V IN
LT1768
Figure 8
INFORMATION
SENSE
T1
U
PGND
GATE
D1
W
L1
U
1768 F08
IN
together with minimum trace between them. If space
constraints prohibit the transformer T1 placement next to
C1, local bypassing (C2) for the center tap of transformer
T1 should be used.
Special attention is also required for the layout of the high
voltage section to avoid any unpleasant surprises. Please
refer to the references for an extensive discussion on high
voltage layout techniques.
Applications Support
Linear Technology invests an enormous amount of time,
resources, and technical expertise in understanding, de-
signing and evaluating backlight solutions for systems
designers. The design of an efficient and compact back-
light system is a study of compromise in a transduced
electronic system. Every aspect of the design is interre-
lated and any design change requires complete re-evalu-
ation for all other critical design parameters. Linear
Technology has engineered one of the most complete test
and evaluation setups for backlight designs and under-
stands the issues and trade-offs in achieving a compact,
efficient and economical customer solution. Linear Tech-
nology welcomes the opportunity to discuss, design,
evaluate, and optimize any backlight system with a cus-
tomer. For further information on backlight designs, con-
sult the references below.
References
1. Williams, Jim. November 1995. A Fourth Generation of
LCD Backlight Technology. Linear Technology Corpora-
tion, Application Note 65.
LT1768
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