LXM1621-03 MICROSEMI, LXM1621-03 Datasheet - Page 7

• Manufacturer Part Number: LXM1621-03
• Manufacturer: MICROSEMI

Specifications of LXM1621-03

• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Pin Count: 22
• Lead Free Status / Rohs Status: Not Compliant

Copyright © 2000
Rev. 1.0a, 2005-02-07
varying lamp current magnitude to adjust light output,
RangeMAX inverters use a fixed lamp current value with a duty
cycle control method.
(continuous lamp current) down to a 2% duty cycle, allowing the
lamp to be dimmed to less than 1% of its full brightness.
design consideration was given to controlling lamp start voltage
to softly start current flow. This eliminates current overshoot
that can result in premature cathode wear and reduce lamp life.
LAMP VOLTAGE & LAMP CURRENT – BURST MODE OPERATION
2.2V
0.25 -
Rather than using the traditional dimming technique of
The lamp current burst width can be modulated from 100%
As can be seen in Trace 3 of Figure 5 photo at right, careful
V
DC
V
BRITE
SYNC
Figure 6 – RangeMAX Simplified Block Diagram
Ramp
Ramp Gen.
I N T E G R A T E D
Figure 3 – 50% Burst Duty Cycle
Comparator
+
-
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: [phone]
Transformer
Driver
I
SENSE
V
SENSE
High Voltage
Transformer
P R O D U C T S
H O W T H E R A N G E M A X W O R K S
Linfinity Microelectronics Division
Microsemi
RangeMAX™
V
V
V
V
HI
HI
LO
LO
HIGHLIGHTS
D
•
•
•
IGITAL
Figure 5 – 2% Burst Duty Cycle (Expanded Time Base)
Integrated brightness control circuit includes a DC
voltage to pulse width converter that minimizes system
design work and system noise susceptibility.
provides a familiar and convenient interface while
reducing the potential for externally induced noise, which
can cause lamp flicker.
An on-board oscillator operates the inverter BURST rate
about 95Hz, well beyond standard 50/60Hz video refresh
rates where the eye can perceive pulsing light.
RangeMAX inverter modules are designed to operate
with the burst frequency synchronized to the video frame
rate. This provides operation with no visible display
disturbances caused by beat frequencies between the
lamps and video frame rates.
D
IMMING
P
RODUCTION
Figure 4 – 2% Burst Duty Cycle
D
UAL
L
AMP
D
CCFL I
ATA
S
NVERTER
HEET
LXM1621-xx
M
ODULE
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