DUAL 5W, DIGITAL DIMMING CCFL INVERTER MODULE
A MICROSEMI COMPANY
PRELIMINARY DATA SHEET
• In applications with no access to a vertical sync, an onboard
oscillator operates the inverter burst rate at about 270Hz. In
this non-synchronous mode, minor display disturbances can
be found under certain video conditions. This performance
may be acceptable for many applications, but
synchronization must be used when no disturbance can be
• Separate feedback loops for lamp current and open circuit
voltage regulation insure reliable strike under all operating
conditions, automatic over-voltage prevention with broken
or failed lamps, and accurate lamp current regulation.
• A single input will accommodate negative and positive
vertical sync pulses at any pulse width.
5V SLEEP VSYNC
Figure 5 - Brightness Control
• The Brightness control may be a voltage output DAC, or
other voltage source as shown in Figure 5. A 2.5V to 5V
Logic Level PWM signal from a micro-controller may
also be used as shown in Figure 5A.
• If synchronization to the video frame rate is desired,
connect the vertical sync pulse from the system video
controller to the VSYNC input. If no video synchronization
is desired, connect VSYNC to ground.
CC F • If you need to turn the inverter ON/OFF remotely, connect
TUB a 2.5V to 5V logic signal to the SLEEP input. If remote
ON/OFF is not needed, connect the SLEEP input to VIN or
other voltage source between 2.5V and 5V.
• Connect VHI to high voltage wire from the lamp. Connect
VLO to the low voltage wire (wire with thinner insulation).
Never connect VLO to circuit ground as this will defeat
lamp current regulation. If both lamp wires have heavy
high voltage insulation, connect the longest wire to VLO.
This wire is typically white.
PW M Signal
1mS to 200µS
0 < P.W. < 100% of period
Also available in single lamp inverters LXM1612-xx-
xx, 5V dual LXM1622-05-xx and Quad Output
LXM1641-01 versions for multiple lamp applications.
Figure 5A - PW M Brightness Control
Copyright © 2000
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570