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 RangeMAXTM
TM (R)
LXMG1621-XX
DIGITAL DIMMING DUAL LAMP CCFL INVERTER MODULE
PRODUCTION DATA SHEET
DESCRIPTION
KEY FEATURES
WWW .Microsemi .C OM
The LXMG1621 Direct DriveTM CCFL (Cold Cathode Fluorescent Lamp) Inverter Modules are specifically designed for driving two lamp LCD backlight displays. Similar to the LXMG1620, the LXMG1621 excels in applications where critical parameters include very wide range dimmability, high efficiency, and reliable fail-safe design in a small form factor. These 12 volt modules are specifically designed with desktop and industrial applications in mind. Unlike the LXMG1620 or any traditional dimming CCFL inverters, the LXMG1621 provides the designer a vastly superior display brightness range. 100:1+ brightness range is achievable with a standard LCD display (see Product Highlight). Our wide range dimming provides exceptional display readability at less than 1% of full brightness, allowing both power savings and low ambient light operating capability(i.e. "night readable"). Digital dimming provides flicker-free brightness control in any wide-range dimming application.
Incorporation of a video synchronization feature allows wide ratio dimming without the display disturbances and interference seen with competitive products. The modules are equipped with a dimming input that permits brightness control from an external potentiometer or DC voltage source. The resultant "burst drive" that energizes the lamp was designed specifically to ensure that no premature lamp degradation occurs (see the "How RangeMAX works" section). The module design is based on a new Direct Drive topology, which provides a number of cost and performance advantages. Microsemi's multiple lamp inverters include a built in connector array for the most common LCD lamp configurations. Other benefits of this new topology are fixed-frequency operation and secondaryside strike-voltage regulation. The LXMG1621 is fully customizable (electronically and mechanically) to specific customer requirements.
RangeMAX Wide Range Dimming 8V to 16V Input Voltage Range Small Form Factor Easy To Use Brightness Control MicroAmp SLEEP Mode Output Short-Circuit Protection And Automatic Strike-Voltage Regulation Fixed Frequency Operation Universal Connector Configuration RoHS Compliant UL 60950 E17590
APPLICATIONS
Hi-Brite Displays Desktop Displays Low Ambient Light Conditions (i.e. Aircraft Cabins, Automobile) Industrial Applications
BENEFITS
High Efficiency Reduces Heating Problems Smooth, Flicker Free 0-100% FullRange 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
IMPORTANT: For the most current data, consult MICROSEMI's website: http://www.microsemi.com Protected By U.S. Patents: 5,923,129; 5,930,121; Patents Pending
PRODUCT HIGHLIGHT
DC Voltage Source
Potentiometer
BRITE
LXMG1621-XX LXMG1621-XX
MODULE ORDER INFO LAMP LAMP RUN VOLTAGE (RMS) PART NUMBER CURRENT
LXMG1621-01 LXMG1621-02 LXMG1621-03 LXMG1621-04
Copyright (c) 2005 Rev. 1.0a, 2006-11-13
Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
1 2 3
3 2 1
UNIVERSAL DIMMING INPUT
VDC OR POTENTIOMETER
7mA 6mA 6.5mA 5mA
500-750 350-550 350-550 470-640
Page 1
Microsemi
RangeMAXTM
TM (R)
LXMG1621-XX
DIGITAL DIMMING DUAL LAMP CCFL INVERTER MODULE
PRODUCTION DATA SHEET
ABSOLUTE MAXIMUM RATINGS (NOTE 1)
WWW .Microsemi .C OM
Input Supply Voltage (VIN)................................................................................................................................-0.3V to 18V Output Voltage, no load....................................................................................................... Internally Limited to 1800VRMS Output Current ........................................................................................................................10mARMS (Internally Limited) Output Power (per lamp) .................................................................................................................................................. 6W Input Signal Voltage (BRITE Input).................................................................................................................-0.3V to 6.5V Input Signal Voltage ( SLEEP , VSYNC)............................................................................................................... -0.3V to VIN Ambient Operating Temperature, zero airflow................................................................................................... 0C to 70C Storage Temperature Range............................................................................................................................. -40C to 85C
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
RECOMMENDED OPERATING CONDITIONS
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
Input Supply Voltage Range (Functional) Input Supply Voltage (Fully Regulated Lamp Current) Output Power (Per Lamp) LXMG1621-01 LXMG1621-02 / 03 LXMG1621-04 Brightness Control Input Voltage Range Lamp Operating Voltage LXMG1621-01 LXMG1621-02 / 03 LXMG1621-04 Lamp Current LXMG1621-01 (Full Brightness - Per Lamp) LXMG1621-02 LXMG1621-03 LXMG1621-04 Operating Ambient Temperature Range
Symbol
VIN
Recommended Operating Conditions Min R.C. Max
8 10.2 12 12 4 2.5 2.75 625 425 550 7.0 6.0 6.5 5.0 16 13.8 5 3 3.5 2.5 750 500 640
Units
V V W W W V VRMS VRMS VRMS mARMS mARMS mARMS MARMS C
PO VBRT_ADJ VLAMP 0.0 500 350 470
IOLAMP TA 0
70
ELECTRICAL CHARACTERISTICS
Unless otherwise specified, these specifications apply over the recommended operating conditions and 25C ambient temperature for the LXMG1621-XX.
Parameter
OUTPUT PIN CHARACTERISTICS Full Brightness Current LXMG1621-01 LXMG1621-02
Symbol
Test Conditions
LXMG1621-XX Min Typ Max
6.3 5.5 5.7 4.5 7.0 6.0 6.5 5.0 0.14 0.035 1500 52 57 1800 62 7.7 6.5 7.1 5.5
Units
IL(MAX) LXMG1621-03 LXMG1621-04 Minimum Lamp Current (Per Lamp) (Notes 2 & 3) Lamp Start Voltage Operating Frequency Copyright (c) 2005 Rev. 1.0a, 2006-11-13
IL(MIN) VLS fO
VBRT_ADJ = 2.5VDC, SLEEP = HIGH, Burst Duty = 100%, VIN = 12VDC VBRT_ADJ = 2.5VDC, SLEEP = HIGH, Burst Duty = 100%, VIN = 12VDC VBRT_ADJ = 2.5VDC, SLEEP = HIGH, Burst Duty = 100%, VIN = 12VDC VBRT_ADJ = 2.5VDC, SLEEP = HIGH, Burst Duty = 100%, VIN = 12VDC VBRT_ADJ = 0VDC, SLEEP = HIGH, Burst Duty = 2%, VIN = 9VDC VBRT_ADJ = -50mVDC, SLEEP= HIGH, Burst Duty =0.5%, VIN = 9VDC 0C < TA < 40C, VIN > 10.8VDC VBRT_ADJ = 2.5VDC, SLEEP= HIGH, VIN = 12VDC
mARMS mARMS mARMS mARMS mARMS mARMS VRMS kHz
ELECTRICALS ELECTRICALS
Microsemi
Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 2
RangeMAXTM
TM (R)
LXMG1621-XX
DIGITAL DIMMING DUAL LAMP CCFL INVERTER MODULE
PRODUCTION DATA SHEET
ELECTRICAL CHARACTERISTICS (CONTINUED)
WWW .Microsemi .C OM
Unless otherwise specified, these specifications apply over the recommended operating conditions and 25C ambient temperature for the LXMG1621-XX.
Parameter
BRITE INPUT Input Current Input Voltage For Max. Lamp Current Input Voltage For Min. Lamp Current (Note 3)
Symbol
Test Conditions
LXMG1621-XX Min Typ Max
-6 -8 2.5 0 -50 -10 2.6 0
Units
IBRT VC VC
VBRT_ADJ = 0V IO(LAMP) = 100% Duty Cycle IO(LAMP) = 2% Duty Cycle IO(LAMP) = 0.5% Duty Cycle
ADC VDC VDC mVDC
SLEEP INPUT
RUN Mode SLEEP Mode Input Current VSYNC CHARACTERISTICS
VSLEEP(HI) VSLEEP(LO)
2.2 -0.3
VIN 0.8
VDC VDC
ISLEEP
VSYNC(HI) VSYNC(LO) ZIN tPW fSYNC IIN(MIN)
SLEEP = 5.0V
70 4.0 -0.3 60 25 49
75
100 6.5 1.0
ADC VDC VDC K s Hz ADC
Logic High Level Logic Low Level Input Impedance Pulse Width (Note 4) Input Frequency
POWER CHARACTERISTICS
66
75 250 150
Sleep Current
VIN = 12VDC, SLEEP < 0.8V
5
50
Note 2: Minimum lamp current required to maintain even light output may vary with display panel. Note 3: See 200:1 Dimming Application section for details. Note 4: The module will be functional with pulse widths much larger than 250s.
FUNCTIONAL PIN DESCRIPTION Conn. CN1 Pin Description
CN1-1 VIN CN1-2 CN1-3 GND CN1-4 Power Supply Return Input Power Supply (8V < VIN < 16V)
ELECTRICALS ELECTRICALS
CN1-5 CN1-6 CN1-7, 8
SLEEP
BRITE VSYNC
ON / OFF Control. (2.2V < SLEEP < VIN = ON, -0.3V < SLEEP < 0.8V = OFF) Brightness Control (-0.3V to 2.5VDC). 2.5VDC gives maximum lamp current. Vertical synchronization input 49Hz < fSYNC < 150Hz
CN2 thru CN5: Refer to Connection Schematic Section
Copyright (c) 2005 Rev. 1.0a, 2006-11-13
Microsemi
Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 3
RangeMAXTM
TM (R)
LXMG1621-XX
DIGITAL DIMMING DUAL LAMP CCFL INVERTER MODULE
PRODUCTION DATA SHEET
PHYSICAL DIMENSIONS
WWW .Microsemi .C OM
LXMG1621-01 / 02 / 03 124mm
4.88 in
CN1 32mm
1.26 in.
CN2, CN3
6mm
0.24 in
Backside Connectors
38mm
1.50 in
48mm
1.89 in
3.0mm 0.08 (0.12in) Grounded Mounting Hole - 2plcs
1.52mm CN4 CN2
0.60 in PCB tolerances 0.5mm
Warning High Voltage Present at all Output Connectors
CN5 CN3
Weight: 23 (g) typ.
LXMG1621-04 124mm
4.88 in
CN1 32mm
1.26 in.
CN2, CN3
6mm
0.24 in
Backside Connectors
38mm
1.50 in
48mm
1.89 in
3.0mm 0.08 (0.12in) Grounded Mounting Hole - 2plcs
MECHANICALS
1.52mm
0.60 in
Warning High Voltage Present at all Output Connectors
PCB tolerances 0.5mm
CN2
CN3
Weight: 23 (g) typ.
All dimensions are in millimeters (inches for reference only)
Copyright (c) 2005 Rev. 1.0a, 2006-11-13
Microsemi
Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 4
RangeMAXTM
TM (R)
LXMG1621-XX
DIGITAL DIMMING DUAL LAMP CCFL INVERTER MODULE
PRODUCTION DATA SHEET
TYPICAL CONNECTION CONFIGURATIONS
CN5
WWW .Microsemi .C OM
CCFL Lamps
CN1
CN5 LXMG1621-01 / 02 /03 CN1
CN4
LXMG1621-01 / 02 /03
CCFL Lamps
Desktop Display
CN4
Desktop Display
CN5
CN5 LXMG1621-01 / 02 /03
CCFL Lamps
CN4
CN4
CCFL Lamps
Desktop Display
Desktop Display
CN5 LXMG1621-01 / 02 /03
CCFL Lamps
CN1
CN5 LXMG1621-01 / 02 /03
CN1
CN4
CCFL Lamps
Desktop Display Desktop Display
LXMG1621-01 / 02 /03
CN1
CN1
APPLICATIONS APPLICATIONS
CN4
* Connectors CN2 and CN3 are on the bottom side of the inverter. View shown is looking through the board
Figure 1 - Connectivity Configuration Examples These examples illustrate six typical LCD wiring configurations that are accommodated by Microsemi's unique connector array. Microsemi inverters have multiple lamp connector styles that are common to the industry, which are duplicated at both ends of the module. This permits over 14 variations of module mounting and interconnectivity configuration.
Copyright (c) 2005 Rev. 1.0a, 2006-11-13
Microsemi
Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 5
RangeMAXTM
TM (R)
LXMG1621-XX
DIGITAL DIMMING DUAL LAMP CCFL INVERTER MODULE
PRODUCTION DATA SHEET
CONNECTION SCHEMATIC
WWW .Microsemi .C OM
CN1 CN2
4 3 2 1 1 2 3
N.C .
VHI1 Inverter Output 1
VHI2 Inverter Output 2
N.C .
1 2 3 4 3 2 1
CN3
CN4
CN5
Figure 2a - LXMG1621-01 / 02 / 03 Connection Schematic
CN1
VHI1 CN2
3 2 1
VHI2 Inverter Output 2 CN3
1 2 3
Figure 2b - LXMG1621-04 Connection Schematic Connectors: CN1 Molex 53261-0871 Mates With
Inverter Output 1
Pins: 50079-8100*, Housing: 51021-0800
*Loose(-8000, Chain) Recommended #26 AwG wiring
Connection for LXMG1621-01 / 02 / 03 CN2, CN3 JST SM04(4.0)B-BHS-1-TB(LF)(SN) or Yeon Ho 20015WR-07A00 CN4, CN5 JST SM03(4.0)B-BHS-1-TB(LF)(SN) or Yeon Ho 20015WR-05A01 Connection for LXMG1621-04 CN2, CN3 JST SM03(4.0)B-BHS-1-TB(LF)(SN) or Yeon Ho 20015WR-05A01 Connection Rules 1. Always install two (2) lamps. Operating with only one lamp may overdrive lamp current at maximum brightness settings. 2. Verify lamp wiring before connecting lamps to the inverter module. Connecting both lamps to one of the two inverter output circuits will result in reduced brightness. The LXMG1621-01 / 02 / 03 module connectors are wired per industry standard. The lamp hot wires (high voltage wires) are always on pin 1 and / or 2, and the cold wire (low voltage wire) is always on pin 3 or 4. 3. The LXMG1621-04 uses the reverse pinout found in some panels. The lamp hot wires (high voltage wires) are on pins 2 and 3 and the cold (low voltage wire) is on pin 1.
Copyright (c) 2005 Rev. 1.0a, 2006-11-13
JST BHR-04VS-1
JST BHR-03VS-1
APPLICATIONS APPLICATIONS
JST BHR-03VS-1
Microsemi
Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 6
RangeMAXTM
TM (R)
LXMG1621-XX
DIGITAL DIMMING DUAL LAMP CCFL INVERTER MODULE
PRODUCTION DATA SHEET
HOW THE RANGEMAX WORKS
LAMP VOLTAGE & LAMP CURRENT - BURST MODE OPERATION
WWW .Microsemi .C OM
Figure 3 - 50% Burst Duty Cycle
Figure 4 - 2% 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 3 of Figure 5 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 5 - 2% Burst Duty Cycle (Expanded Time Base)
Comparator VBRITE 0.25 2.2VDC Ramp + LAMP High Voltage Transformer VHI
HIGHLIGHTS
*
Ramp Gen.
Transformer Driver VLO
VHI VSENSE VSYNC ISENSE
VLO
Figure 6 - RangeMAX Simplified Block Diagram
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. * 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.
DESCRIPTION DESCRIPTION
Copyright (c) 2005 Rev. 1.0a, 2006-11-13
Microsemi
Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
LAMP
Page 7
RangeMAXTM
TM (R)
LXMG1621-XX
DIGITAL DIMMING DUAL LAMP CCFL INVERTER MODULE
PRODUCTION DATA SHEET
HOW THE RANGEMAX WORKS (CONTINUED)
HIGHLIGHTS (CONTINUED)
WWW .Microsemi .C OM
*
In applications with no access to a vertical sync, the inverter burst frequency can be allowed to "free run" at 95Hz. In this non-synchronous mode, minor display disturbances may be found under certain video conditions. This performance is 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.
TYPICAL APPLICATION
12V 2.5VDC < 10k BRITE VIN VHI2 VHI1
*
LXMG1621-XX 0 5V SLEEP VSYNC
GND
VLO
VSYNC Figure 7- Brightness Control
PWM Signal 4.99k from System
4.99k* P.W. < 100s 0 < P.W. < 100% of period
* use 4.99k for 5V PWM amplitude, 15k for 3.3V PWM amplitude, and omit for 2.5V PWM amplitute.
4.7F
BRITE
LXMG1621xx
The brightness control may be a simple 10k potentiometer or a voltage output DAC. A PWM signal from a microcontroller may also be used with a suitable filter such as shown in figure 8. * If synchronization to the video frame rate is desired, connect the vertical sync pulse from the system video controller to the appropriate VSYNC input. If no video synchronization is desired, connect VSYNC to ground. * If you need to turn the inverter ON/OFF remotely, connect a 3V or 5V logic signal to the SLEEP input. If remote ON/OFF is not needed, connect the SLEEP input to VIN or any other voltage greater than 2.2VDC. * Connect VHI to high voltage wire from the lamp. Connect VLO to the low voltage wire (wire with thinner insulation). If both lamp wires have heavy high voltage insulation, connect the longest wire to VLO. VLO is connected directly to ground (GND pin) on the inverter PCB. Always insure a good lamp return by using a wire. Do not rely on a chassis ground connection.
RangeMAX INVERTERS
Figure 8 - PWM Brightness Control
Also available in single lamp inverters are the LXMG1612-12-xx or LXMG1615-xx-xx, as well as the 12V dual lamp LXMG1623-xx-xx, LXMG1622-12-xx, and the Quad output LXMG1643-12-6x versions for multiple lamp applications.
A APPLICATIONS
Copyright (c) 2005 Rev. 1.0a, 2006-11-13
Microsemi
Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 8
RangeMAXTM
TM (R)
LXMG1621-XX
DIGITAL DIMMING DUAL LAMP CCFL INVERTER MODULE
PRODUCTION DATA SHEET
WIDER DIMMING APPLICATION
WWW .Microsemi .C OM
IOLAMP(mA)
The following application defines techniques capable of delivering dimming ranges in the 250:1 range. As is widely understood, these techniques will provide general capabilities and actual system performance will vary with panel design, CCFTs, ambient temperature and a number of other variables outside the control of the inverter. These methods can be used in conjunction with other techniques such as lamp heating and matching. Wide ratio (250:1) dimming can be accomplished using the Microsemi inverter in two ways:
7
0.7 .14 .070
-100mV
0V
2.5V
1. By varying the input voltage on the brightness pin as VBRT_ADJ(V) indicated in Figure 9. Caution must be exercised when applying negative voltage to the brightness control input. Figure 9 - Average Lamp Current vs. VBRITE Voltage (per Lamp) Applying more then -300mV to any inverter input will cause inverter malfunction (see Absolute Maximum Ratings). 2. By making a resistor value change on the module. Remove R61 for maximum dimming range or increase R61 value to desired minimum dim range setting (see figure 10). Care should be exercised since at a low enough dim setting the inverter will be unable to detect that the lamp has started and will initiate lamp strike (kickoff) voltage. This will result in Backside of Module lamp flicker. For repeatable low light levels the BRITE input DC supply must be a very clean stable voltage source, at low dim inputs. R63 R51 R60 If you plan to completely remove R61 it is recommended that R62 you ensure that a minimum voltage above zero remain on the R61 R31 BRITE input to prevent the above flicker problem. This U9 U7 Q10 minimum voltage may need to be adjusted for each individual inverter module. If you are using a pot to control the BRITE R57 R54 R53 input then a separate trim pot on the low side would accomplish Q11 T1 R48 the same goal. R89 C37 Both methods discussed will provide a lower duty cycle operation than is necessary in a 100:1 dimming application. Figure 10 - Locating The Resistor on the LXMG1621-XX Careful consideration should be made with regard to display quality at these dimming levels. At very low brightness levels, even very small amounts of noise on the VBRITE line can cause flicker on the display, so special care must be given to grounding, filtering, and shielding the inverter from the digital logic and clock signals.
CN2 C35 R59 R58 C33 C32 R52 R55 R50 C30 R22 R56 C39 R49
APPLICATIONS APPLICATIONS
Copyright (c) 2005 Rev. 1.0a, 2006-11-13
Microsemi
Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 9
RangeMAXTM
TM (R)
LXMG1621-XX
DIGITAL DIMMING DUAL LAMP CCFL INVERTER MODULE
PRODUCTION DATA SHEET
WWW .Microsemi .C OM
NOTES
N NOTES
PRODUCTION DATA - Information contained in this document is proprietary to Microsemi and is current as of publication date. This document may not be modified in any way without the express written consent of Microsemi. Product processing does not necessarily include testing of all parameters. Microsemi reserves the right to change the configuration and performance of the product and to discontinue product at any time.
Copyright (c) 2005 Rev. 1.0a, 2006-11-13
Microsemi
Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 10


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