LXM1612-05.pdf

A
LINFINITY
M I C R O S E M I
LXM1612-05-xx
5V Highly-Integrated, Digital Dimming CCFL Inverter Module
C O M P A N Y
P RELIMINARY D ATASHEET
KEY FEATURES
DESCRIPTION
Input Voltage Range. The modules
convert DC voltage from the system
battery or AC adapter directly to highfrequency, high-voltage waves required
to ignite and operate CCFL lamps. A
12V input inverter is also available
(LXM1612-12-xx)
Direct Drive Technology.
The
module design is based on a new Direct
Drive topology, which provides a
number of cost and performance advantages.
Additional Features. Other benefits of
this new topology are fixed-frequency
operation and secondary-side strikevoltage regulation and all LXM1612-05xx modules feature both open and
shorted lamp protection.
IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com
! RangeMAX Wide Range
Dimming
! Single 5V Input Voltage
! Fully Integrated Direct Drive
And Dimming Control
! Single Sided PCB Layout
! Easy To Use Brightness
Control
! MicroAmp SLEEP Mode
! Output Short-Circuit
Protection And Automatic
Strike-Voltage Regulation
! Fixed Frequency Operation
APPLICATIONS
! Notebook And Sub-Notebook
Computers
! Portable Instrumentation
! Desktop Displays
! Low Ambient Light
Conditions (i.e. Aircraft
Cabins, Automobile)
PRODUCT HIGHLIGHT
DC Voltage
Source
BENEFITS
PW M
Signal
3
Potentiom eter
1
2
BRITE
U
N IV E R S A L
DC
,
IM M IN G
OR
!
! Smooth, Flicker Free 1-100%
Full-Range Brightness
Control Gives Your Product
A High Quality Image
! Output Open Circuit Voltage
Regulation Minimizes Corona
Discharge For Long Life And
High Reliability
! Power Efficient. “Low
Brightness” Capability Allows
For Advanced Power
Management
IN P U T
P O T E N T IO M
ETER
LXM1612-05
"P W M ", V
D
PACKAGE ORDER INFO
PART NUMBER
LXM1612-05-01
LXM1612-05-02
LXM1612-05-03
Copyright  2000
Rev. 0.5h, 2001-09-14
W W W. Microsemi .COM
RangeMAX Wide Range Dimming,
Single Output Inverter. The LXM161205-xx series of Direct Drive™ CCFL
(Cold Cathode Fluorescent Lamp)
Inverter Modules are specifically
designed for driving LCD backlight
lamps.
RangeMAX
Digital
Dimming
Technique. Digital Dimming provides
flicker-free brightness control in any
wide-range dimming application.
The modules are equipped with a
dimming input that permits brightness
control from either an external potentiometer, DC voltage source, or PWM
signal. The resultant “burst drive” that
energizes the lamp was designed
specifically to ensure that no premature
lamp degradation occurs.
INVERTER MATES DIRECTLY
TO PANEL CONNECTORS
JST SM02(8.0)B-BHS-1-TB
BHR-03VS-1
JST SM02B-BHSS-1-TB
BHSR-02VS-1
Honda QZ-19-A3MYL #02
QZ-19-3F01
OUTPUT CONNECTOR
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
A
LINFINITY
M I C R O S E M I
LXM1612-05-xx
5V Highly-Integrated, Digital Dimming CCFL Inverter Module
C O M P A N Y
P RELIMINARY D ATASHEET
ABSOLUTE MAXIMUM RATINGS (NOTE 1)
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.
W W W. Microsemi .COM
Input Signal Voltage (VIN1) ................................................................................................................................-0.3V to 6.5V
Output Voltage, no load..........................................................................................................Internally Limited to 1800VRMS
Output Current.........................................................................................................................8.0mARMS (Internally Limited)
Output Power................................................................................................................................................................... 6.0W
Input Signal Voltage (BRITE Input) .........................................................................................................-0.3V to VIN1+0.3V
Input Signal Voltage ( SLEEP , VSYNC Inputs) ............................................................................................-0.3V to VIN1+0.3V
Ambient Operating Temperature, zero airflow..................................................................................................... 0°C to 70°C
Storage Temperature Range .............................................................................................................................. -40°C to 85°C
FUNCTIONAL PIN DESCRIPTION
CONN
PIN
DESCRIPTION
CN1 (Molex 53261-0890) Mates with 51021-0800 housing, 50079-8100 pins
CN1-1
CN1-2
CN1-3
CN1-4
VIN1
Main Input Power Supply (4.5V < VIN1 < 5.5V
GND
Power Supply Return
CN1-5
SLEEP
ON/OFF Control. (2.1V < SLEEP < VIN1 = ON, 0V < SLEEP < 0.8V = OFF, SLEEP Floating = OFF)
CN1-6
BRITE
Brightness Control (0.0V to 2.5VDC). 2.5VDC gives maximum lamp current.
CN1-7
BRITE RTN
Analog Ground. Use for BRITE signal return ONLY.
CN1-8
VSYNC
Vertical Synchronization Input. 2.5 to 5.0V Logic Level. (20Hz < fSYNC < 200Hz)
CN2 for LXM1612-05-01 and -02 (JST SM02(8.0)B-BHS-1-TB or SM02B-BHSS-1-TB)
CN2-1
VHI
High voltage connection to high Side of lamp. Connect to lamp terminal with shortest lead length.
DO NOT connect to Ground.
CN2-2
VLO
Connection to low side of lamp. Connect to lamp terminal with longer lead length.
DO NOT connect to Ground
CN2 for LXM1612-05-03 (Honda QZ-19-A3MYL#02)
CN2-3
VHI
High voltage connection to high side of lamp. Connect to lamp terminal with shortest lead length.
DO NOT connect to Ground.
CN2-1
VLO
Connection to low side of lamp. Connect to lamp terminal with longer lead length.
DO NOT connect to Ground
PHYSICAL DIMENSIONS
LXM1612-05-XX
PACKAGE DATA
-01
3.0mm DIA .
" CN-1
0.63in.
0.13in.
0.5in.
16mm
3.3mm
CN-2
12.7mm
!
1 !
G ROUNDED M OUNTING H OLE
0.66in.
3.0mm DIA .
-03
-02
1!
SM02B-BHSS-1-T B
(JST )
M OUNTING H OLE
SM02(8.0)B-BHS-1-T B
(JST )
126mm
1
3
Honda QZ-19-A3MYL #02
4.96in.
3.64in.
92.5m m
16.75mm
0.06in.
1.52mm
0.315in .
8.0mm
W arning
High Voltage Present at all
Output Connectors
W eight: 12.5 (g) typ .
Copyright  2000
Rev. 0.5h, 2001-09-14
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 2
LINFINITY
A
M I C R O S E M I
LXM1612-05-xx
5V Highly-Integrated, Digital Dimming CCFL Inverter Module
C O M P A N Y
P RELIMINARY D ATASHEET
Parameter
Symbol
Input Supply Voltage Range (Fully Regulated
Lamp Current)
Input Supply Voltage Range (Functional)
Output Power
Brightness Control Input Voltage Range
Lamp Operating Voltage
Lamp Current (Full Brightness)
Operating Ambient Temperature Range
Recommended Operating Conditions
Min
R.C.
Max
VIN1
PO
VBRT_ADJ
VLAMP
IOLAMP
TA
4.5
5
5.5
4.35
5
3.5
2.5
535
5.8
5.65
4.0
VIN
620
0.0
450
0
Units
V
W
V
VRMS
mARMS
°C
70
W W W. Microsemi .COM
RECOMMENDED OPERATING CONDITIONS (R.C.)
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.
ELECTRICAL CHARACTERISTICS
Unless otherwise specified, the following specifications apply over the recommended operating condition and ambient temperature of
25°C except where otherwise noted.
Parameter
#
Full Bright Lamp Current
IL(MAX)
Min. Average Lamp Current
(Note 2)
IL(MIN)
VLS
Operating Frequency
fO
IBRT
VBRT_ADJ=2.5VDC, SLEEP=HIGH,
Burst Duty=100%, VIN1=5VDC
VBRT_ADJ=0VDC, SLEEP=HIGH, Burst Duty=2.0%,
VIN1=5VDC
0°C <TA < 70°C, VIN1 > 5.0VDC
5.2
5.8
6.4
0.12
mARMS
mARMS
1500
1650
1800
VRMS
63
68
73
kHz
VBRT_ADJ=0VDC
-685
-728
-775
µADC
VBRT_ADJ=2.5VDC
-260
-282
-305
µADC
2.35
2.40
VDC
VBRT_ADJ=2.5VDC, SLEEP=HIGH, VIN1=5.0V
Input Voltage for Max. Lamp Current
VBRT_ADJ
IO(LAMP)=100% Duty Cycle
2.30
Input Voltage for Min. Lamp Current
VBRT_ADJ
IO(LAMP)= Minimum Duty Cycle
0.0
VDC
SLEEP INPUT
RUN Mode
VSLEEP(HI)
VIN1=4.5V
1.9
2.1
VIN1
VDC
SLEEP Mode
VSLEEP(LO)
VIN1=5.5V
-5.0
1.9
2.0
VDC
Input Current
I SLEEP
SLEEP=5.0V
SLEEP=0V
390
410
435
µADC
0.0
0.0
0.0
µADC
VSYNCH(HI)
VIN1=4.5V
1.50
2.5
5.0
VDC
VSYNCH(LO)
VIN1=5.5V
VSYNC CHARACTERISTICS
Logic High Level
#
Units
-3.0
0.0
1.2
VDC
Input Impedance
ZIN
25
27
29
KΩ
Input Frequency
fSYNC
20
200
Hz
10
µADC
POWER CHARACTERISTICS
Sleep Current
IIN(MIN)
VIN1=5VDC, SLEEP=0.0V
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 5.8mARMS)
Copyright  2000
Rev. 0.5h, 2001-09-14
0.0
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
0.5
Page 3
ELECTRICALS
#
LXM1612-05-xx
Min
Typ
Max
BRITE INPUT
Input Current
#
Test Conditions
OUTPUT PIN CHARACTERISTICS
Lamp Start Voltage
#
Symbol
A
LINFINITY
M I C R O S E M I
C O M P A N Y
LXM1612-05-xx
5V Highly-Integrated, Digital Dimming CCFL Inverter Module
P RELIMINARY D ATASHEET
HOW RANGEMAX WORKS
W W W. Microsemi .COM
LAMP VOLTAGE & LAMP CURRENT – Burst Mode Operation
Figure 2 – 2% Burst Duty Cycle
Figure 1 – 50% Burst Duty Cycle
Rather than using the traditional dimming technique of varying
lamp current magnitude to adjust light output, RangeMAX
inverters use 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 2% duty cycle, allowing the
lamp to be dimmed to less than 1% of its full brightness.
As can be seen in Trace 4 of Figure 3 photo at right, 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.
Figure 3 – 2% Burst Duty Cycle (Expanded Time Base)
High Voltage
Transformer
Comparator
V BRITE
V HI
+
0.25 2.5V DC
Transformer
Driver
Ramp
LAMP
-
DESCRIPTION
Ramp Gen
V SENSE
V SYNC
I SENSE
V LO
Figure 4 – RangeMAX Block Diagram
Copyright  2000
Rev. 0.5h, 2001-09-14
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 4
A
LINFINITY
M I C R O S E M I
C O M P A N Y
LXM1612-05-xx
5V Highly-Integrated, Digital Dimming CCFL Inverter Module
P RELIMINARY D ATASHEET
HOW RANGEMAX WORKS (CONTINUED)
!
Integrated 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.
!
In applications with no access to a vertical sync., an onboard
oscillator operates the inverter burst rate at about 250Hz. 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.
!
A single input will accommodate negative and positive
vertical sync pulses at any pulse width.
!
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.
W W W. Microsemi .COM
Highlights
TYPICAL APPLICATION
5V
DAC or
Pot
BRITE
VIN1
!
The brightness control may be a voltage output DAC, digital
resistor or a simple 10k potentiometer. If desired, an
additional series resistor with the 10k potentiometer can be
used to set a higher minimum brightness setting as shown in
Figure 5. A 2.5V to 5V Logic Level PWM signal from a
micro-controller may also be used as shown in Figure 5A.
!
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
to 2.5V to 5V logic signal to the SLEEPinput.
!
Connect VHI to high voltage wire from the lamp. Connect
VLO to the low voltage wire (wire with thinner insulation).
Never connect VLO to circuit ground as this will defeat lamp
current regulation. If both lamp wires have heavy high
voltage insulation, connect the longest wire to VLO. This
wire is typically white.
VHI
10k
CCFL
TUBE
LXM1612-05-xx
R
0V
BRITE RTN
VSYNC
5V
SLEEP
GND
VLO
V SYNC
Figure 5 - Potentiometer Brightness Control
PW M Signal
from System
BRITE
P.W .
LXM1612-05-xx
2ms
0 < P.W. < 100% of period
Figure 5A - PW M Brightness Control
LXM1612-05-XX OUTPUT CURRENT ADJUST
R40
R17
R36
R37
R39
R12
R14
C16
R11
C8
U1
R5
R38
R15
C11
C12
C5
C6
C21
R35
R32
R41
R7
C15
R2
R20
R31
C9
C2
C4
C7
R16
Not Used
Not Used
Not Used
499K 1%
178K 1%
78.7K 1%
R3
C3
D1
Copyright  2000
Rev. 0.5h, 2001-09-14
R12
2.00K 1%
2.61K 1%
2.74K 1%
2.74K 1%
2.74K 1%
2.74K 1%
R4
U3
R21
Output Current
7.0mA
6.0mA
5.8mA
5.0mA
4.0mA
3.0mA
R34
R6
C14
C13
C10
C17
R33
R16
R10
R13
Figure 6- Component Replacement Locations
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 5
DESCRIPTION
R30
U4
D2
The LXM1612-05 output current can be adjusted by changing the
value of two resistors on the PCB. The following table shows the
approximate new output current values:
A
LINFINITY
M I C R O S E M I
C O M P A N Y
LXM1612-05-xx
5V Highly-Integrated, Digital Dimming CCFL Inverter Module
P RELIMINARY D ATASHEET
W W W. Microsemi .COM
NOTES
NOTES
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. 0.5h, 2001-09-14
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 6