MICROSEMI LXM1614

A
M I C R O S E M I
RangeMAX™
LXM1614-14-11
DUAL DIMMING, EXTENDED TEMPEERATURE CCFL INVERTER MODULE
C O M P A N Y
P RELIMINARY D ATASHEET
LXM1614 series of Direct Drive™ CCFL
(Cold Cathode Fluorescent Lamp)
Inverter Modules is specifically designed
for driving LCD backlight lamps.
Although similar to the RangeMAX
LXM1612 wide range dimming inverters,
the LXM1614 family offers two separate
brightness controls for lamp current
amplitude and duty cycle.
This
innovation of dual brightness control with
extended dimming, combined with
Linfinity’s high efficiency Direct Drive
topology, provides the industry’s most
feature rich, small form factor inverter
available. The wide range dimming provides exceptional display readability at
less than 1% of full brightness, allowing
both power savings and low ambient light
operating capability.
The
inverters
provide
brightness
adjustments utilizing standard lamp current
amplitude control as well as supporting
Linfinity’s RangeMAX wide range
dimming technique. Combining both
brightness controls into a single inverter
supports the “self heating” lamp technology by using a “boost” current
feature and still offers duty cycle control
for low brightness operation.
This
controlled
overdrive
capability
eliminates the need for traditional
resistive heater wire methods to ensure
light output at extremely low
temperatures. The LXM1614 brightness
controls support temperature monitoring
with look-up table applications by
accepting either a PWM input or DC
voltage. Large panel lamps with greater
thermal inertia can also utilize this
“instant-bright” feature and minimize
warm up time.
Dual Drive Dimming Control.
Independent Brightness
Controls For Lamp Current
Amplitude and Duty Cycle
RangeMAX 1-100% Wide
Range Dimming with
Controlled Overdrive Boost
On-Board Thermister automatically limits maximum
lamp current
Supports Wide Input Voltage
Range 9-16V
High Efficiency, Single Stage
Direct Drive Topology
-40°C to +85°C Ambient
Temperature Operation
Output Open/Short Circuit
Protection
Up to 1800V Output Voltage
Capability
Single side PCB Component
Layout
W W W . Microsemi . COM
Dual Drive, RangeMAX Wide Range
Dimming, Single Output Inverter. The
Self Heating And High
(continued next page)
Pressure Lamp Technology
IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com
Automotive Navigation, GPS
Systems, Auto PC
Extended Cold Temperature
Operation
Aircraft Cabin Displays
Low Ambient Light Conditions
Requiring Wide Range
Dimming
“Instant On” To Full
Brightness For Large LCD
Backlight Panels
Industrial Notebook And
Workstations
LXM1614-14-11
Controlled overdrive mode of
LXM1614 Inverter accelerates
lamp warm-up time to provide
maximum light output even in
extreme temperature environments
Copyright  2000
Rev. 0.3b,2000-11-20
PART NUMBER
OUTPUT CONNECTOR
INVERTER MATES DIRECTLY TO
PANEL CONNECTORS
LXM1614-14-11
JST SM02(8.0)B-BHS-1-TB
BHR-03VS-1
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
A
M I C R O S E M I
RangeMAX™
LXM1614-14-11
DUAL DIMMING, EXTENDED TEMPEERATURE CCFL INVERTER MODULE
C O M P A N Y
P RELIMINARY D ATASHEET
Direct Drive Technology.
An on-board thermister monitors the inverter’s relative
The module design is based on the Direct Drive topology,
temperature and limits the maximum allowable lamp
current. This current limit automatically protects the lamp which provides a number of cost, performance, and form
and inverter as a function of temperature which helps factor advantages. The LXM1614 series inverters eliminate
the classic resonant inductor/capacitors and integrate the
control the system during Boost mode.
wide range dimming logic into the controller.
RangeMAX Digital Dimming Technique.
Digital dimming provides flicker-free brightness control
in any wide range dimming application. Dimming ratios
greater than 100:1 can be achieved. A video synchronization feature allows wide ratio dimming without the
display disturbances and interference seen with competitive
products. The resultant “burst drive” that energized the
lamp was designed specifically to ensure that no premature
lamp degradation occurs. Even in overdrive boost mode,
the waveform is carefully controlled to minimize the
effects that are detrimental to lamp life. Individual panel
specifications should be referenced for specific thermal and
electrical parameters.
Additional Features.
Other benefits of this new topology are fixed-frequency
operation and secondary-side strike-voltage regulation.
Strike-voltage regulation minimizes corona discharge in the
output transformer and related circuitry, providing longer life
and higher reliability. All LXM1614 modules feature both
open and shorted lamp protection. The dual drive LXM1614
is fully customizable (electronically and mechanically) to
specific customer requirements.
W W W . Microsemi . COM
Input Supply Voltage (VIN) ...................................................................................................................................-0.3V to 17V
Output Voltage, no load...........................................................................................................Internally Limited to 1800VRMS
Output Current................................................................................................................... 16mARMS (<2 [email protected]<25°C)
Output Power................................................................................................................................................................... 10W
Input Signal Voltage (BRITE, BOOST) ................................................................................................................. -0.3V to VIN
Input Signal Voltage (SLEEP, VSYNC).................................................................................................................... -0.3V to VIN
Ambient Operating Temperature, zero airflow .................................................................................................. -40°C to 85°C
Storage Temperature Range ............................................................................................................................ -40°C to 85°C
Note 1: Exceeding these ratings could cause damage to the device. All voltages are with respect to Ground. Currents are positive into, negative out of
specified terminal.
This module has been designed to operate over a wide range of input and output conditions. However, best efficiency and performance will be obtained if
the module is operated under the condition listed in the ‘R.C.’ Column. Min. and Max. columns indicate values beyond which the inverter, although
operational, will not function optimally.
Symbol
VIN Voltage Range
VIN
Output Power
PO
Recommended Operating Conditions
Min
R.C.
Max
9.0
Brightness Control Input Voltage Range
VBRT_ADJ
0.0
BOOST Control Input Voltage Range
VBST_ADJ
0.0
Lamp Operating Voltage
VLAMP
Lamp Current Full Brightness
IOLAMP
TA
Operating Ambient Temperature Range
Copyright  2000
Rev. 0.3b,2000-11-20
Units
16.0
V
6.0
W
5.0
V
5.0
V
900
VRMS
4.0
9.0
mARMS
-40
85
°C
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
LXM1614-14-11
Parameter
Page 2
A
M I C R O S E M I
RangeMAX™
LXM1614-14-11
DUAL DIMMING, EXTENDED TEMPEERATURE CCFL INVERTER MODULE
C O M P A N Y
P RELIMINARY D ATASHEET
Unless otherwise specified, these specifications apply over the recommended operating conditions and TA = -40 to 85°C ambient temperature for the
LMX1614-14-11.
Parameter
Lamp Current, Full Boost
IL(BOOST)
Lamp Current, No Boost
IL(BOOST)
Lamp Start Voltage
Units
9.0
mARMS
4.0
mARMS
.12
mARMS
VIN=9V, VBRT_ADJ = 5V, VBST_ADJ = 5V, TA per
Figure 2
VIN=9V, VBRT_ADJ = 5V, VBST_ADJ = 0V, TA per
Figure 2
VBRT_ADJ = 0V
1800
VBRT_ADJ = 5V
TFAULT
VRMS
75
KHz
1.0
SEC
BRITE INPUT
Linear Dim Control Range
Input Current
VBRT
IBRT
0.5
VBRT_ADJ = 0V
VBRT_ADJ = 5V
Input Voltage for Max. Lamp Current
VBRT_ADJ
IO(LAMP) = 100% Duty Cycle
Input Voltage for Min. Lamp Current
VBRT_ADJ
IO(LAMP) = Minimum Duty Cycle
4.5
10
10
VDC
µADC
µADC
4.5
5.0
VDC
0
0.5
VDC
BOOST INPUT
Linear Dim Control Range
Input Current
VBST
IBOOST
0.5
VBST_ADJ = 0V
VBST_ADJ = 5V
4.5
10
10
VDC
µADC
µADC
Input Voltage for Max. Boost Current
VBST_ADJ
4.5
5.0
VDC
Input Voltage for Min. Boost Current
VBST_ADJ
0
0.5
VDC
RUN Mode
VSLEEP
2.4
VIN
VDC
OFF Mode
VSLEEP
0.8
VDC
SLEEP INPUT
Input Current
IL(MIN)
FO
Fault Timeout
LXM1614-14-11
Min
Typ Max
VLS
Operating Frequency
Test Conditions
OUTPUT PIN CHARACTERISTICS
Min. Average Lamp Current (Note 2)
Symbol
W W W . Microsemi . COM
IISLEEP
0
SLEEP=5V
SLEEP=0V
390
410
435
0
uA
VSYNC CHARACTERISTICS
VSYNC (HI)
2.4
Logic Low Level
VSYNC (LO)
-0.3
Input Impedance
ZIN
Input Frequency
FVSYNC
Output Burst Rate
FBURST
5.5
VDC
0.8
VDC
10
50
VSYNC=0V, Free Run Frequency
KΩ
300
167
Hz
Hz
Note 2: Minimum lamp current required to maintain even light output may vary with display panel.
Average RMS current = (burst duty cycle) X (burst amplitude of full lamp current)
Copyright  2000
Rev. 0.3b,2000-11-20
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 3
ELECTRICALS
Logic High Level
A
M I C R O S E M I
RangeMAX™
LXM1614-14-11
DUAL DIMMING, EXTENDED TEMPEERATURE CCFL INVERTER MODULE
C O M P A N Y
P RELIMINARY D ATASHEET
Conn.
Pin
W W W . Microsemi . COM
Description
CN1 (Molex 53261-0890)*
CN1-1,2
VIN
Main Input Power Supply (9V to 16V)
CN1-3,4
GND
Power Supply Return
CN1-5
SLEEP > 2.4V (Backlight on), < 0.8V (Backlight off), IISLEEP=400µA @ 5.0V
CN1-6
BOOST Lamp Current Amplitude Control (0.5-4.5VDC) 4.5VDC gives maximum boost
CN1-7
BRITE Brightness Control (0.5- 4.5VDC) 4.5VDC gives maximum lamp current
CN1-8
VSYNC
Vertical Synchronization Input (50 < fSYNC < 300Hz), minimum pulse width 10µS
CN2 (JST SM02(8.0)B-BHS-1-TB)
CN2-1
CN2-2
VOUT1
VOUT2
High Voltage CCFL Lamp Supply
High Voltage CCFL Lamp Return
* LX9501 Mating Connector Assembly Available
4.724 in.
0.394 in.
120m m
10m m
C N -1
0.905 in.
0.787 in.
23m m
20m m
0.118 in.
C N -2
3m m
0.394 in.
10m m
5.118 in.
130m m
0.280 in.
7.1m m
W eight: 12.5(g) typ.
0.0393 in.
1m m
MECHANICALS
Copyright  2000
Rev. 0.3b,2000-11-20
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 4
A
M I C R O S E M I
RangeMAX™
LXM1614-14-11
DUAL DIMMING, EXTENDED TEMPEERATURE CCFL INVERTER MODULE
C O M P A N Y
P RELIMINARY D ATASHEET
H igh Voltage
T ransformer
W W W . Microsemi . COM
VOUT1
V BST
C omparator
T ransformer
D river
LAMP
G ain &
Summing
.5 4.5V DC
V SEN SE
I SEN SE
V BR T
R amp
.5 4.5V DC
V SYN C
+
-
R amp G en.
& PLL
T emperature
Sense
I/V
VOUT2
– RangeMAX Simplified Block Diagram
HIGHLIGHTS
•
Copyright  2000
Rev. 0.3b,2000-11-20
•
In applications with no access to a vertical sync, an
onboard oscillator operates the inverter burst rate at
about 170Hz. In this non-synchronous mode, minor
display disturbances can be found under certain video
conditions. This performance may be acceptable for
many applications, but synchronization must be used
when no disturbance can be tolerated.
• Separate feedback loops for lamp current and open
circuit voltage regulation insure reliable strike under all
operating conditions, automatic over-voltage prevention
with broken or failed lamps, and accurate lamp current
regulation.
• A single input will accommodate negative and positive
vertical sync pulses at any pulse width.
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 5
DESCRIPTION
Integrated dual brightness control circuit includes a DC
voltage to pulse width converter that minimizes system
design work and system noise susceptibility. This provides
a familiar and convenient interface while reducing the
potential for externally induced noise, which can cause
lamp flicker.
• 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. In this synchronous mode, the inverter burst
rate operates at twice the video refresh rate, well beyond
standard 50/60Hz video refresh rates where the eye can
perceive pulsing light.
A
M I C R O S E M I
RangeMAX™
LXM1614-14-11
DUAL DIMMING, EXTENDED TEMPEERATURE CCFL INVERTER MODULE
C O M P A N Y
P RELIMINARY D ATASHEET
W W W . Microsemi . COM
LAMP VOLTAGE & LAMP CURRENT – BURST MODE OPERATION
– LXM1614 Combines Current Amplitude and Digital Techniques
The LXM1614 provides both lamp current amplitude control
(BOOST) and a brightness control (BRITE) for dimming.
Please see following sections for dimming and amplitude boost
control. To achieve extremely wide dimming ranges, rather
than only using the traditional dimming technique of varying
lamp current magnitude to adjust light output, RangeMAX
inverters utilize a fixed lamp current value with a duty cycle
control method.
The lamp current burst width can be modulated from 100%
(continuous lamp current) down to a 3% duty cycle, allowing
the lamp to be dimmed to less than 2% of its full brightness
As can be seen in Trace 4 of Figure 5, careful 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.
– 50% Burst Duty Cycle
– 2% Burst Duty Cycle
DESCRIPTION
– 2% Burst Duty Cycle (Expanded Time Base)
Copyright  2000
Rev. 0.3b,2000-11-20
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 6
A
M I C R O S E M I
RangeMAX™
LXM1614-14-11
DUAL DIMMING, EXTENDED TEMPEERATURE CCFL INVERTER MODULE
C O M P A N Y
P RELIMINARY D ATASHEET
DUAL DIMMING CAPABILITY
As seen in the Brightness vs. Time graphs, the boost mode
operation can improve the performance of cold cathode
florescent lamps in any LCD application by reducing the time it
takes to warm up lamps to their optimum operating
temperature. This feature is helpful in large LCD multi-lamp
monitors as well as automotive or industrial extreme
temperature applications.
The “boost” control is used to provide a timed overdrive
mode to maximize light output over temperature. After a panel
is characterized with a profile of the user’s application (such as
desired light output as a function of ambient light and
temperature), the appropriate boost level and duration of the
boost can be set. Further wide range dimming control is
provided by the Brite input dimming function.
W W W . Microsemi . COM
6 -
DESCRIPTION
-
Copyright  2000
Rev. 0.3b,2000-11-20
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 7
A
M I C R O S E M I
RangeMAX™
LXM1614-14-11
DUAL DIMMING, EXTENDED TEMPEERATURE CCFL INVERTER MODULE
C O M P A N Y
P RELIMINARY D ATASHEET
WIDE RANGE DIMMING FUNCTION
AMPLITUDE BOOST FUNCTION
Dimming can be controlled by a DC voltage (like a voltage
output DAC) or by a PWM signal (5V logic level PWM signal
from a micro controller). The PWM signal should be 400Hz to
4kHz, 0V to 5V, 0% to 100% duty cycle.
The Boost Function Control signal levels are the same as
the Dimming Control. Less than 0.5V provides 4mA
maximum lamp current while 4.5V on Boost provides “max
boost” with a max lamp current of 9mA. Please note that
these maximum lamp current levels are protected by the onboard thermister which limits the maximum lamp current
automatically as a function of temperature as seen in Figure
9.
Brightness
Lamp Current (mArms)
control range
W W W . Microsemi . COM
control range
100%
boost mode
9
VIN = 9V
4
no boost mode
Typical curve for 5.8” panel. Other
panels may be different.
1%
BRITE
0.0 V
0.5 V
4.5 V
IBOOST
5.0 V
0.0
- Brightness as a function of the BRITE control (CN1-7)
0.5
4.5
5.0
– Maximum lamp current as a function of the Boost control
(CN1-6)
Lamp Current (mArms)
9.0
7.5
VIN = 9V
5.5
4.0
DESCRIPTION
Typical curve for 5.8” panel.
Other panels may be different.
Temp
-40
0
25
85°C
– Maximum lamp current as a function of ambient
temperature
Copyright  2000
Rev. 0.3b,2000-11-20
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 8
A
M I C R O S E M I
RangeMAX™
LXM1614-14-11
DUAL DIMMING, EXTENDED TEMPEERATURE CCFL INVERTER MODULE
C O M P A N Y
P RELIMINARY D ATASHEET
•
9V -16V
BOOST
V IN
B R IT E
V OUT1
CCFL
T U BE
LX M 1614-14-1 1
S LEE P
0V
S YN C
G ND
VOUT2
2.5V
V SYN C
F ig ure 1 1 - B rightness C ontro l
P W M S ig nal
from System
The BRITE/BOOST control may be a voltage output
DAC, or other voltage source as shown in Figure 11. A
5V Logic Level PWM signal from a micro-controller may
also be used as shown in Figure 12.
• If synchronization to the video frame rate is desired,
connect the vertical sync pulse from the system video
controller to the VSYNC input. If no video synchronization
is desired, connect VSYNC to ground.
• If you need to turn the inverter ON/OFF remotely, connect
a 2.4V to 5V logic signal to the SLEEP input. If remote
ON/OFF is not needed, connect the SLEEP input to VIN or
other voltage source between 2.4V and 5V.
• Connect VOUT1 to the high voltage supply wire from the
lamp. Connect VOUT2 to the high voltage return wire from
the lamp.
W W W . Microsemi . COM
BOOST
BR ITE
P.W .
LXM 1614-14-11
2.5m S to 250µ S
Also available in other wide range dimming single lamp
inverters LXM1612-xx-xx, LXM1615, Dual Output
LXM1621-01, LXM1622-xx-xx and Quad Output
LXM1641-01 versions for multiple lamp applications.
0 < P.W. < 100% of period
F ig u re 1 2 - P W M B righ tn ess C on tro l
APPLICATION
Preliminary Data – Information contained in this document is pre-production data and is proprietary to LinFinity. It may
not be modified in any way without the express written consent of LinFinity. Product referred to herein is offered in
sample form only and LinFinity reserves the right to change or discontinue this proposed product at any time.
Copyright  2000
Rev. 0.3b,2000-11-20
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 9