LXMG1627-12-44 Microsemi Analog Mixed Signal Group, LXMG1627-12-44 Datasheet - Page 5

• Manufacturer Part Number: LXMG1627-12-44
• Description: MOD INVERTER CCFL DUAL 4W 12V
• Manufacturer: Microsemi Analog Mixed Signal Group
• Series: PanelMatch™r
• Type: Inverters for CCFL and UV Lampsr

Specifications of LXMG1627-12-44

• Voltage - Input: 12V
• Output: 1400V
• Size / Dimension: 4.28" L x 0.88" W x 0.40" H (108.7mm x 22.35mm x 10.2mm)
• Mounting Type: Chassis Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Copyright © 2008
Rev. 1.1, 2008-12-09
0V to
2.5V
0 < P.W. < 100% of period
TM
500k
Figure 1A – PWM Brightness Control
DAC or
Pot
2.5µs to 125µS
from System
PWM Signal
(Output current set to maximum)
Figure 2 – Max Output Current
BRITE
SLEEP
Figure 1 – Brightness Control
SET
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, 800-877-6458, Fax: [phone]
H
H
(SET
L
L
P.W.
1
LXMG1627-12-44
BRITE
SET
L=GND; H=Open
NC
SLEEP
1
SET
1
H
H
and SET
L
L
LXMG1627-12-44
2
12V
V
SET
NC
IN
12V
5.0mA
5.5mA
6.0mA
6.5mA
2
V
BRITE
GND
IN
2
LXMG1627-12-44
Inputs)
GND
RMS
RMS
RMS
RMS
LAMP
LAMP
V
V
LO
HI
LO
HI
ONE OF
T Y P I C A L A P P L I C A T I O N
TWO
One of
Two
CCFL
TUBE
Analog Mixed Signal Group
CCFL
TUBE
®
Microsemi
PanelMatch™ RangeMAX™ LXMG1627-12-44
12V Dual 4W CCFL Programmable Inverter Module
The brightness control may be a voltage output DAC or other
voltage source, a digital pot or 500K manual pot. The inverter
contains an internal 191k pull-up resistor in series with 43.2k
to 4.2V to bias the pot (see block diagram). A PWM Logic
level signal (figure 1A) may be used up to 5V; however the
inverter will reach maximum current at less than 100% duty
cycle. This can be calculated as approximately 2.3V divided
by the logic high voltage level; with 3.3V logic level this
corresponds to about 70% duty cycle for maximum lamp
current.
If you need to turn the inverter ON/OFF remotely, connect to
TTL logic signal to the
Connect V
V
Never connect V
current regulation.
voltage insulation, connect the longest wire to V
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 manufacturers. Generally the best lamp
lifetime
manufacturer’s 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 an 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.
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 user’s responsibility since 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) the inverter will
attempt to strike the lamp for about 1.2 seconds, without
success the inverter will shutdown. In order to restart the
inverter it is necessary to toggle the sleep input or cycle the
V
connected to ground the inverter will immediately shutdown.
LO
IN
input supply. If either high side lamp output is directly
to the low voltage wire (wire with thinner insulation).
2
P
correlates
HI
inputs allow the user the flexibility to adjust the
RODUCTION
1
to high voltage wire from the lamp. Connect
and SET
LO
to circuit ground as this will defeat lamp
If both lamp wires have heavy high
with
SLEEP
2
(see Figure 2) inputs to select the
D
driving
ATASHEET
input.
the
CCFL
LO
. This wire
Since the
at
the
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