Microsemi
Analog Mixed Signal Group
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 8
Copyright © 2007
Rev. 1.2, 2010-08-20
WWW.Microsemi .COM
RangeMAX
LXMG1621-xx
DIGITAL DIMMING DUAL LAMP CCFL INVERTER MODULE
TM
®
HOW THE RANGEMAX WORKS (CONTINUED)
HIGHLIGHTS (CONTINUED)
• In applications with no access to a vertical sync, the
inverter burst frequency can be allowed to “free run” at
95Hz. In this non-synchronous
mode, minor display
disturbances may be found under certain video conditions.
This performance is acceptable for many applications, but
synchronization must be used when no disturbance can be
tolerated.
• 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.
TYPICAL APPLICATION
LXMG1621-xx
12V
V
SYNC
V
SYNC
GND
V
HI1
V
LO
BRITE
Figure 7- Brightness Control
V
IN
SLEEP
5V
0
< 10k
2.5V
DC
V
HI2
P.W.
< 100µs
BRITE
LXMG1621-
xx
0 < P.W. < 100% of period
PWM Signal
from System
Figure 8 - PWM Brightness Control
4.7µF
4.99k*
4.99k
* use 4.99k for 5V PWM amplitude, 15k for 3.3V PWM
amplitude, and omit for 2.5V PWM amplitute.
• The brightness control may be a simple 10k potentiometer
or a voltage output DAC. A PWM signal from a micro-
controller may also be used with a suitable filter such as
shown in figure 8.
• If synchronization to the video frame rate is desired,
connect the vertical sync pulse from the system video
controller to the appropriate V
SYNC
input. If no video
synchronization is desired, connect V
SYNC
to ground.
• If you need to turn the inverter ON/OFF remotely, connect
a 3V or 5V logic signal to the
SLEEP
input. If remote
ON/OFF is not needed, connect the
SLEEP
input to V
IN
or
any other voltage greater than 2.2V
DC
.
• Connect V
HI
to high voltage wire from the lamp. Connect
V
LO
to the low voltage wire (wire with thinner insulation).
If both lamp wires have heavy high voltage insulation,
connect the longest wire to V
LO
. V
LO
is connected directly
to ground (GND pin) on the inverter PCB. Always insure
a good lamp return by using a wire. Do not rely on a
chassis ground connection
.
RangeMAX INVERTERS
Also available in single lamp inverters are the
LXMG1612-12-xx or LXMG1615-xx-xx, as well as the
12V dual lamp LXMG1623-xx-xx, LXMG1622-12-xx,
and the Quad output LXMG1643-12-6x versions for
multiple lamp applications.
A
A
P
P
P
P
L
L
I
I
C
C
A
A
T
T
I
I
O
O
N
N
S
S