LXMG1626-12-45 Microsemi Analog Mixed Signal Group, LXMG1626-12-45 Datasheet - Page 5

• Manufacturer Part Number: LXMG1626-12-45
• Description: MOD INVERTER CCFL DUAL 3W 12V
• Manufacturer: Microsemi Analog Mixed Signal Group
• Series: PanelMatch™r
• Type: Inverters for CCFL and UV Lampsr

Specifications of LXMG1626-12-45

• Voltage - Input: 12V
• Output: 1500V
• Size / Dimension: 4.45" L x 1.18" W x 0.26" H (113mm x 30mm x 6.5mm)
• Mounting Type: Chassis Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Copyright © 2005
Rev.1.0, 2006-10-18
* Under some conditions the second lamp will also shutdown, this is especially
Both Lamps Open
Normal Operation
Both Lamps High
Lamp(s) Status
One Lamp Open
One Lamp High
Side Short to
Side Short to
true if the inverter draws an arc going open or when shorted.
Ground
Ground
TM
0 < P . W . < 100 % of period
Figure 1A – PWM Brightness Control
10 µs to 200 µS
Figure 2 – FAULT Output Operation
500K
PWM Signal
from System
(Output current set to maximum)
DAC or
Pot
Figure 1 – Brightness Control
BRITE
SLEEP
SET
P
1
.
LXMG1626-12-45
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: [phone]
FAULT
BRITE
W
SET
NC
FAULT
High
High
High
High
SLEEP
Low
.
LXMG1626-12-45
12V
FAULT
V
IN1
NC
`
12V
V
GND
Normal @ ~½ lamp current*
Normal @ ~½ lamp current*
IN1
Normal full lamp current
BRITE
Inverter Operation
GND
LXMG1626-12-45
V
V
V
HI1
HI2
LO
Shutdown
Shutdown
V
V
V
HI2
HI1
LO
T Y P I C A L A P P L I C A T I O N
Integrated Products
®
Microsemi
PanelMatch™
12V Dual 3W 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 215K pull-up to 3V to bias the
pot.
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
lamps. Connect V
(wire with thinner insulation). Never connect V
ground as this will defeat lamp current regulation. If both
lamp wires have heavy high voltage insulation, connect the
longest wire to V
Use the SET input to change the desired maximum output
current. Generally the best lamp lifetime correlates with
driving the CCFL at the manufactures nominal current
setting.
Although the SET pin is designed such that just leaving it
open or grounding it is all that is needed to program the
output current, it 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.
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 input could be used to overdrive the
lamp temporarily to facilitate faster lamp warm up at initial
lamp turn on. Of course, any possible degradation of lamp
life from such practices is the user’s responsibility since not
all lamps are designed to be overdriven.
Input connector (CN1-8) FAULT signal which is normally
low will toggle high to indicate that an output fault
condition has occurred as summarized in the table to the left
figure 2. FAULT will toggle high if one or both lamps are
open or short circuited. If only one lamp opens, or its high
side shorts to ground then the other lamp should continue to
operate with the FAULT signal going high.
open and/or both lamps are shorted the FAULT will toggle
high if it is not already high and the inverter output will
shutdown. Also if either low side connection of the lamps
is shorted to ground, or the lamps are shorted high side to
low side, FAULT will go high and the inverter will
shutdown. In order to restart the inverter after a fault it is
necessary to toggle the SLEEP input or cycle the V
supply. In fault induced shutdown mode the inverter will
draw about 15mA from V
A 3.3V Logic Level PWM signal from a micro-
P
RODUCTION
HI1
and V
LO
. This wire is typically white.
LO
HI2
to the low voltage wire lamp return
IN1
D
SLEEP
to high voltage wires from the
ATASHEET
supply.
input.
LXMG1626-12-45
If both lamps
LO
to circuit
IN1
input
In
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