ETC LXM1644-12-61

PanelMatch™
I N T E G R A T E D
P R O D U C T S
LXM1644-12-61
12V Quad 6W CCFL Programmable Inverter Module
P RELIMINARY D ATASHEET
KEY FEATURES
DESCRIPTION
For applications not requiring wide
range dimming, amplitude control results
in lower ripple on the input supply and
reduced
potential
transient
noise
generation. Many STN type panels are
particularly well suited for current
amplitude dimming.
The modules convert DC voltage from
the system battery or AC adapter directly
to high frequency, high-voltage waves
required to ignite and operate CCFL
lamps.
The LXM1644-12-61 inverter is intended for panel assemblies where lamp
pairs share close proximity with one
another and a common return (low side)
wire.
Other benefits of this new topology
are stable fixed-frequency operation,
secondary-side strike-voltage regulation
and both open/shorted lamp protection
with fault timeout.
IMPORTANT: For the most current data and a panel to inverter cross reference, consult MICROSEMI’s website:
http://www.microsemi.com
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The LXM1644-12-61 is a Quad 6W
Output Direct Drive™ CCFL (Cold
Cathode Fluorescent Lamp) Inverter
Module specifically designed for driving
LCD backlight lamps. It is ideal for
driving typical 12.1” to 18.1” TFT panels.
The modules are available with a
dimming input that permits brightness
control from either a DC voltage source or
a PWM signal or external Potentiometer.
The maximum output current is externally
programmable over a range of 10 to 16mA
in 1mA steps to allow the inverter to
properly match to a wide array of LCD
panel lamp current specifications.
LXM1644
modules
unlike
the
LXM1643 series does not provide wide
range ‘burst’ mode dimming, rather
dimming is provided by amplitude control
of the output current waveform, this limits
the potential dim range to typically less
than 5:1.
Externally Programmable
Maximum Output Current
Easy to Use Brightness
Control
Analog Current Amplitude
Dimming Method
Output Open/Short-Circuit
Protection and Timeout
Fixed Frequency Operation
Rated From -20 to 70°C
UL 60950 E175910
APPLICATIONS
High Brightness Displays
Desktop Displays
Industrial Display Controls
BENEFITS
Compact, Low Profile
Design
Programmable output
current allows inverter to
mate with a wide variety of
LCD panel’s specifications
PRODUCT HIGHLIGHT
Universal Dimming Input PWM, VDC, or
DC Voltage
Source
Potentiometer
PWM
Signal
"
LXM1644-12-61
Selectable Maximum Output Current 10mA to 16mA RMS
PACKAGE ORDER INFO
Copyright  2002
Rev. 0.5a, 2003-01-20
ART NUMBER
OUTPUT CONNECTORS
LXM1644-12-61
Two JST SM04(4.0)B-BHS-1-TB
INVERTER MATES DIRECTLY TO
PANEL CONNECTORS
JST BHR-04VS-1
Microsemi
Integrated Products
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
PanelMatch™
I N T E G R A T E D
LXM1644-12-61
12V Quad 6W CCFL Programmable Inverter Module
P R O D U C T S
P RELIMINARY D ATASHEET
Input Signal Voltage (VIN1).....................................................................................................................................-0.3V to 15V
Input Power ....................................................................................................................................................................... 30W
Output Voltage, no load ............................................................................................................ Internally Limited to 2000VRMS
Output Current (each output) ......................................................................................................9.5mARMS (Internally Limited)
Output Power (each output) ............................................................................................................................................. 6.0W
Input Signal Voltage ( SLEEP Input) ..................................................................................................................... -0.3V to VIN1
Input Signal Voltage (BRITE) ...............................................................................................................................-0.3V to 5.5V
Ambient Operating Temperature, zero airflow.....................................................................................................-20°C to 70°C
Operating Relative Humidity, non-condensing ................................................................................................................ ≤ 90%
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.
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ABSOLUTE MAXIMUM RATINGS (NOTE 1)
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.
Parameter
Symbol
Input Supply Voltage Range (Fully Regulated
Lamp Current)
Input Supply Voltage Range (Functional)
Output Power (each lamp)
Linear BRITE Control Input Voltage Range¹
Lamp Operating Voltage
Lamp Current (Each pair, Full Brightness)
Operating Ambient Temperature Range
VIN1
PO
VBRT_ADJ
VLAMP
IOLAMP
TA
Recommended Operating Conditions
Min
R.C.
Max
10.8
12
13.2
10.2
12
5.0
13.8
6.0*
2.0
720
16
70
0.65 to 0.9
530
10
-20
625
Units
V
W
V
VRMS
mARMS
°C
*Total output power must not exceed 12W per lamp pair. Higher voltage lamps may require the maximum output current to be set lower 16mA
¹ The minimum VBRT ADJ voltage depends on the panel characteristics, depending on the panel it can vary from 0.65V to 0.9V
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
`
Symbol
Test Conditions
LXM1644-12-61
Min
Typ
Max
Units
OUTPUT PIN CHARACTERISTICS
IL(MAX)
Full Bright Lamp Current (two lamps)
IL(MAX)
Full Bright Lamp Current (two lamps)
IL(MAX)
Full Bright Lamp Current (two lamps)
IL(MAX)
Output Current pair of Lamps to pair of
Lamps Deviation
ILL%DEV
Min. Average Lamp Current
(each output)
Lamp Start Voltage
Operating Frequency
IL(MIN)
VLS
fO
VBRT_ADJ > 2.0VDC, SLEEP > 2.0V, VIN1 = 12VDC
ISET1 = Ground, ISET2 = Ground
VBRT_ADJ > 2.0VDC, SLEEP > 2.0V, VIN1 = 12VDC
ISET1 = Ground, ISET2 = Open
VBRT_ADJ > 2.0VDC, SLEEP > 2.0V, VIN1 = 12VDC
ISET1 = Open, ISET2 = Ground
VBRT_ADJ > 2.0VDC, SLEEP > 2.0V, VIN1 = 12VDC
ISET1 = Open, ISET2 = Open
VBRT_ADJ > 2.0VDC, SLEEP > 2.0V, VIN1 = 12VDC
ISET1 = Open, ISET2 = Open
VBRT_ADJ ≤0.5VDC, SLEEP > 2.0V, VIN1 = 12VDC
ISET1 = ISET2 = Ground
-20°C < TA < 70°C, VIN1 > 10.8VDC
VBRT_ADJ = 2.5VDC, SLEEP > 2.0V, VIN1 = 12V
9
10
11
mARMS
10.8
12
13
mARMS
12.8
14
15
mARMS
14.7
16
17
mARMS
3
10
%
5.5²
1500
1650
69
72
mARMS
VRMS
75
kHz
² The inverter is capable of a lower output current than may be recommended by the panel manufacturer. It is the user’s responsibility to set the minimum brightness
(BRITE) input at or above the panel specification for minimum current.
Copyright  2002
Rev. 0.5a, 2003-01-20
Microsemi
Integrated Products
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 2
ELECTRICALS
Full Bright Lamp Current (two lamps)
PanelMatch™
I N T E G R A T E D
P R O D U C T S
LXM1644-12-61
12V Quad 6W CCFL Programmable Inverter Module
P RELIMINARY D ATASHEET
Parameter
`
Symbol
`
`
LXM1644-12-61
Min
Typ
Max
Units
-300
50
µADC
µADC
BRITE INPUT
Input Current
`
Test Conditions
IBRT
VBRT_ADJ = 0VDC
VBRT_ADJ = 3VDC
Minimum Input for Max. Lamp Current
VBRT_ADJ
IO(LAMP) = Maximum Lamp Current
Minimum Input for Min. Lamp Current
VBRT_ADJ
IO(LAMP) = Minimum Lamp Current
2.0
2.05
0.65*
VDC
VDC
SLEEP INPUT
RUN Mode
VSLEEP
2.0
VIN1
VDC
SLEEP Mode
VSLEEP
-0.3
0.8
VDC
0.4
V
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ELECTRICAL CHARACTERISTICS (CONTINUED)
Unless otherwise specified, the following specifications apply over the recommended operating condition and ambient temperature of
25°C except where otherwise noted.
SET1,2 INPUT
SET1,2 Low Threshold
VL
Input Current
ISET
VSET ≤ 0.4V
-300
µA
POWER CHARACTERISTICS
Sleep Current
IIN(MIN)
Run Current
IRUN
η
Efficiency
VIN1 = 12VDC, SLEEP < 0.8V
0.0
VIN1 = 12VDC, SLEEP ≥ 2.0V, ISET1 = Open
ISET2 = Ground, VLAMP = 625VRMS
VIN1 = 12VDC, SLEEP ≥ 2.0V, ISET1 = Open
ISET2 = Ground, VLAMP = 625VRMS
10
30
µADC
1750
mADC
85
%
* The Inverter is capable of a lower output current than may be recommended by the panel manufacturer. It is the user’s responsibility to set the minimum brightness
(BRITE) input at or above the panel specification for minimum current. This is likely greater than the 0.65V minimum input.
FUNCTIONAL PIN DESCRIPTION
CONN
PIN
DESCRIPTION
CN1 (Molex 53261-1290) Mates with 51021-1200 housing, 50079-8100 pins. Mates with LX9508 input cable assembly
CN1-1,2,3
VIN1
Main Input Power Supply (10.8V < VIN1 < 13.2V)
CN1-4,5,6
GND
Power Supply Return
CN1-7
AGND
Analog Signal Ground
CN1-8
NC
CN1-9
SLEEP
CN1-10
BRITE
CN1-11
SET1
SET1 MSB Connecting this pin to ground decreases the output current (see Table 1)
CN1-12
SET2
SET2 LSB Connecting this pin to ground decreases the output current (see Table 1)
No Connect
ON/OFF Control. (0V < SLEEP < 0.8 = OFF, SLEEP >= 2.0V = ON
Brightness Control (0.65V to 2.0V). 2.0VDC gives maximum lamp current.
CN2,3-1
VHI1
High voltage connection to high Side of lamp. Connect to lamp terminal with shortest lead length.
DO NOT connect to Ground.
CN2,3-2
VHI2
High voltage connection to high Side of lamp. Connect to lamp terminal with shortest lead length.
DO NOT connect to Ground.
CN2,3-3
NC
Open Pin
CN2,3-4
VLO
Connection to low side of lamps. Connect to lamp terminal with longer lead length.
DO NOT connect to Ground
Copyright  2002
Rev. 0.5a, 2003-01-20
Microsemi
Integrated Products
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 3
ELECTRICALS
CN2, CN3 (JST SM04(4.0)B-BHS-1-TB)
PanelMatch™
I N T E G R A T E D
LXM1644-12-61
12V Quad 6W CCFL Programmable Inverter Module
P R O D U C T S
P RELIMINARY D ATASHEET
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TABLE 1
OUTPUT CURRENT SETTINGS (TWO LAMPS)
SET1
(Pin 11)
Open*
Open*
Ground
Ground
SET2
(Pin 12)
Open*
Ground
Open*
Ground
Nominal Output Current
16.0mA
14.0mA
12.0mA
10.0mA
* If driven by a logic signal it should be open collector or open drain only, not a voltage source.
PHYSICAL DIMENSIONS
7.40in
188mm
7.16in
0.23in
182mm
0.15in
6mm
4mm
0.15in
CN-1
W
4mm
1.41in.
36mm
W
3.70in
0.15in
94mm
4mm
SM04(4.0)B-BHS-1-TB
(JST)
GROUNDED MOUNTING HOLES
3.18MM ±.08 DIA.
Warning
High Voltage Present at
high side of both
Transformers and Output
Connectors
0.315in.
8.0mm Max
PCB tolerances ± 0.5mm
0.060in.
Weight: 44g typ.
1.52mm
SIMPLIFIED BLOCK DIAGRAM
High Voltage T ransformers
VHI
10K
V BR IT E
V IN 1
SET 1
Z
Z
O C SEN SE
PACKAGE DATA
10K
LAMP
+3V
O V SEN SE
+3V
SET 2
V HI
Controller and
Transform er
Driver
LAMP
+3V
10K
I SENSE
V LO
O ne of two
Copyright  2002
Rev. 0.5a, 2003-01-20
Microsemi
Integrated Products
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 4
PanelMatch™
I N T E G R A T E D
P R O D U C T S
LXM1644-12-61
12V Quad 6W CCFL Programmable Inverter Module
P RELIMINARY D ATASHEET
The brightness control may be a voltage output DAC or
other voltage source, a digital pot or 20K manual pot. The
inverter contains an internal 10K pull-up to 3V to bias the
pot, add a 1.8K to 3.9K resistor to set the lower threshold
voltage. A 3.3V Logic Level PWM signal from a microcontroller may also be used as shown in Figure 1A.
12V
DAC or
Pot
V IN 1
BRITE
V H1
V H2
20K
LXM1644-12-61
Rx*
If you need to turn the inverter ON/OFF remotely, connect
to TTL logic signal to the SLEEP input.
SLEEP
SET 1
SET 2
G ND
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.
O ne of
two
NC
NC
V LO
*Set Rx from 1.8K to 3.9K depending on panel
minimum lamp current requirements
Figure 1 – Brightness Control
(Output current set to maximum)
PW M Signal
from System
Use the SET1 and SET2 (see Figure 2) inputs to select the
desired maximum output current. Using these two pins in
combination allows the inverter to match a wide variety of
panels from different manufactures. Generally the best
lamp lifetime correlates with driving the CCFL at the
manufactures nominal current setting. However the SET1
and SET2 inputs allow the user the flexibility to adjust the
current to the maximum allowable output current to
increase panel brightness at the expense of some reduced
lamp life.
BRITE
P.W .
LXM1644-12-61
10us to 125uS
26% < P.W. < 100% of
period
Figure 1A – PWM Brightness Control
12V
BRITE
V IN1
LXM1644-12-61
SLEEP
SET 1
SET 2
GND
One
of two
L
10.0mARMS
H
12.0mARMS
L
14.0mARMS
H
16.0mARMS
L=GND; H=Open
Figure 2 – Max Output Current (Two Lamps)
(SET1 and SET2 Inputs)
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 a 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. In
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 users
responsibility since not all lamps are designed to be
overdriven.
The inverter has a built in fault timeout function. If the
output return is open (lamp disconnected or broken) or
shorted the inverter will attempt to strike the lamp for
several seconds. After about a second without success the
inverter will shutdown. In order to restart the inverter it is
necessary to toggle the sleep input or cycle the VIN1 input
supply. In the timeout shutdown mode input drain current
will be about 8mA.
Microsemi
Integrated Products
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 5
APPLICATION
L
L
H
H
Copyright  2002
Rev. 0.5a, 2003-01-20
WWW . Microsemi .C OM
TYPICAL APPLICATION
PanelMatch™
I N T E G R A T E D
P R O D U C T S
LXM1644-12-61
12V Quad 6W CCFL Programmable Inverter Module
P RELIMINARY D ATASHEET
WWW . Microsemi .C OM
NOTES
NOTES
Preliminary Data – Information contained in this document is pre-production data and is
proprietary to Microsemi. It may not be modified in any way without the express written
consent of Microsemi. Product referred to herein is offered in sample form only and
Microsemi reserves the right to change or discontinue this proposed product at any time.
Copyright  2002
Rev. 0.5a, 2003-01-20
Microsemi
Integrated Products
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 6