LXMG1617A-12-42 MICROSEMI, LXMG1617A-12-42 Datasheet - Page 5

• Manufacturer Part Number: LXMG1617A-12-42
• Description: CCFL Inverter Single Lamp 3.5W 80KHz
• Manufacturer: MICROSEMI

Specifications of LXMG1617A-12-42

• Number Of Lamps: Single
• Typical Input Voltage: 12 V
• Typical Lamp Start Voltage: 1450 Vrms
• Typical Lamp Operating Voltage: 550 Vrms
• Maximum Dimming: 100:1(Typ)
• Operating Temperature: -30 to 80 °C

Copyright © 2007
Rev. 1.1, 2010-02-26
0V to
2.0V
TM
0 < P.W. < 100% of period
500k
DAC or
Pot
Figure 1A – PWM Brightness Control
10µs to 500µS
from System
PWM Signal
(Output current set to maximum)
Figure 2 – Max Output Current
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, 800-877-6458, Fax: [phone]
Figure 1 – Brightness Control
BRITE
SLEEP
SET
(SET
H
H
L
L
P.W.
1
LXMG1617A-12-4x
BRITE
SET
NC
L=GND; H=Open
SLEEP
1
SET
1
LXMG1617A-12-4x
and SET
H
H
L
L
12V
2
V
SET
NC
IN
5.0mA
5.5mA
6.0mA
6.5mA
12V
2
V
BRITE
GND
LXMG1617A-12-4x
2
IN
Inputs)
GND
RMS
RMS
RMS
RMS
V
V
LO
HI
V
T Y P I C A L A P P L I C A T I O N
V
LO
HI
TUBE
Analog Mixed Signal Group
CCFL
CCFL
TUBE
®
Microsemi
PanelMatch™ "A Series"
12V 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 215K pull-up to 3V to bias the pot, if
desired; add a resistor to set the lower threshold voltage above
the absolute minimum dim level capability. 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 2V divided by
the logic high voltage level; with 3.3V logic level this
corresponds to about 60% 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
to the low voltage wire (wire with thinner insulation). Never
connect V
regulation.
insulation, connect the longest wire to V
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.
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 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) or shorted the inverter
will attempt to strike the lamp up to about one second, after
which (without success) the inverter will shutdown, in this
mode the inverter will draw about 8mA from V
restart the inverter it is necessary to toggle the sleep input or
cycle the V
P
2
RODUCTION
LO
correlates
HI
inputs allow the user the flexibility to adjust the
IN
to high voltage wire from the lamp. Connect V
to circuit ground as this will defeat lamp current
If both lamp wires have heavy high voltage
1
input supply.
and SET
with
SLEEP
2
D
(see Figure 2) inputs to select the
ATASHEET
driving
input.
LXMG1617A-12-4x
the
LO
CCFL
. This wire is
IN
. In order to
at
the
LO
In
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