LXMG1617-03-2X MICROSEMI [Microsemi Corporation], LXMG1617-03-2X Datasheet - Page 5

• Manufacturer Part Number: LXMG1617-03-2X
• Description: 3.3V 2.2W CCFL Programmable Inverter Module
• Manufacturer: MICROSEMI [Microsemi Corporation]

Copyright © 2002
Rev. 1.1, 2006-09-19
TM
0.45V
2.0V
to
0 < P.W. < 100% of period
Figure 1A – PWM Brightness Control
1.8K
20K
DAC or
Pot
10µs to 125µS
PWM Signal
from System
(Output current set to maximum)
Figure 2 – Max Output Current
Figure 1 – Brightness Control
BRITE
SLEEP
SET
(SET
H
H
L
L
P.W.
1
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: [phone]
L=GND; H= Open
BRITE
LXMG1617-03-2x
SET
NC
SLEEP
1
SET
and SET
H
H
L
L
1
LXMG1617-03-2x
3.3V
2
V
SET
NC
IN1
3.3V
3.5mA
4.0mA
4.5mA
5.0mA
V
2
IN1
BRITE
GND
2
LXMG1617-03-2x
Inputs)
GND
RMS
RMS
RMS
RMS
V
V
LO
HI
V
V
LO
HI
T Y P I C A L A P P L I C A T I O N
TUBE
CCFL
CCFL
TUBE
Integrated Products
®
Microsemi
P
P
a
a
n
n
e
e
l
l
M
M
3.3V 2.2W CCFL Programmable Inverter Module
a
a
t
t
c
c
The brightness control may be a voltage output DAC or
other voltage source, a digital pot or 20K manual pot. The
inverter contains an internal 10K pull-up to 3V to bias the
pot add a 1.8K resistor to set the lower threshold voltage.
A 3.3V Logic Level PWM signal from a micro-controller
may also be used as shown in Figure 1A.
If you need to turn the inverter ON/OFF remotely, connect
to TTL logic signal to the
Connect V
V
Never connect V
lamp current regulation. If both lamp wires have heavy
high voltage insulation, connect the longest wire to V
This wire is typically white.
Use the SET
desired maximum output current. Using these two pins in
combination allows the inverter to match a wide variety of
panels from different manufactures.
lamp lifetime correlates with driving the CCFL at the
manufactures nominal current setting. However the SET
and SET
current to the maximum allowable output current to
increase panel brightness at the expense of some reduced
lamp life.
Although the SET pins are designed such that just leaving
them open or grounding them is all that is needed to set the
output current, they can also be actively set. Using a open
collector or open drain logic signal will allow you to reduce
the lamp current for situations where greater dim range is
required, as an example in nighttime situations.
conjunction with a light sensor or other timer the panel
could be set to higher brightness (maximum output current)
for daytime illumination and lower brightness (minimum or
typical output current) at nighttime. Since the dim ratio is a
factor of both the burst duty cycle and the peak output
current, using this technique the effective dim ratio can be
increased greater than the burst duty cycle alone.
Conversely the SET inputs could be used to overdrive the
lamp temporarily to facilitate faster lamp warm up at initial
lamp turn on. Of course any possible degradation on lamp
life from such practices is the users responsibility as not all
lamps are designed to be overdriven.
the output is open (lamp disconnected or broken) or shorted
the inverter will attempt to strike the lamp for several
seconds. After about 2 seconds without success the inverter
will shutdown.
necessary to toggle the sleep input or cycle the V
supply.
h
h
LO
™
™
to the low voltage wire (wire with thinner insulation).
The inverter has a built in fault timeout function. If
P
RODUCTION
2
inputs allow the user the flexibility to adjust the
HI
1
to high voltage wire from the lamp. Connect
and SET
LO
In order to restart the inverter it is
to circuit ground as this will defeat
2
D
(see Figure 2) inputs to select the
SLEEP
ATASHEET
input.
LXMG1617-03-2x
Generally the best
IN1
input
LO
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