LXM1618-12-42 MICROSEMI, LXM1618-12-42 Datasheet - Page 5

• Manufacturer Part Number: LXM1618-12-42
• Manufacturer: MICROSEMI

Specifications of LXM1618-12-42

• Operating Temperature Classification: Commercial
• Pin Count: 10
• Lead Free Status / Rohs Status: Not Compliant

Copyright © 2002
Rev. 1.0b, 2005-01-17
to 2.0V
0.65V
I N T E G R A T E D
~26% < P.W. < 100% of
2.7K
Figure 1A – PWM Brightness Control
20K
DAC or
Pot
(Output current set to maximum)
10µs to 125µS
Figure 2 – Max Output Current
PW M Signal
from System
Figure 1 – Brightness Control
BRITE
SLEEP
SET
period
(SET
H
H
L
L
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: [phone]
1
BRITE
P.W .
L=GND; H=Open
SET
NC
LXM1618-12-4x
SLEEP
1
SET
and SET
H
H
1
L
L
LXM1618-12-4x
12V
2
V
SET
IN1
NC
5.0mA
5.5mA
6.0mA
6.5mA
12V
V
2
GND
IN1
2
BRITE
P R O D U C T S
Inputs)
LXM1618-12-4x
GND
RMS
RMS
RMS
RMS
V
V
LO
HI
V
V
T Y P I C A L A P P L I C A T I O N
LO
HI
CCFL
TUBE
Integrated Products
CCFL
TUBE
Microsemi
PanelMatch™
12V 4W CCFL Programmable Inverter Module
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 2.7K 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.
the desired maximum output current. Using these two pins
in combination allows the inverter to match a wide variety
of panels from different manufactures. Generally the best
lamp lifetime and efficiency correlates with driving the
CCFL at the manufactures nominal current setting.
However the SET
flexibility to adjust the current to the maximum allowable
output current to increase panel brightness at the expense
of some reduced lamp life.
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. In 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 the peak output
current, using this technique the effective dim ratio can be
increased. 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 inverter has a built in fault timeout function. If 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
LO
to the low voltage wire (wire with thinner insulation).
Use the SET
Although the SET pins are designed such that just
P
RODUCTION
HI
to high voltage wire from the lamp. Connect
1
LO
In order to restart the inverter it is
1
and SET
and SET
to circuit ground as this will defeat
D
SLEEP
ATASHEET
2
(see Figure 2) inputs to select
2
inputs allow the user the
input.
LXM1618-12-4x
IN1
input
LO
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