MICROSEMI LXM1620-01

LXM1620-01
D I R E C T D R I V E D U A L L A M P CCFL I N V E RT E R M O D U L E
T
H E
I
N F I N I T E
P
O W E R
O F
I
P
N N O VA T I O N
R E L I M I N A R Y
DESCRIPTION
The Dual Output Module Ideal for
Desktop and Industrial Applications. The
LXM1620 Direct DriveTM Cold Cathode Fluorescent Lamp (CCFL) Inverter is a single module designed to drive two lamps and is targeted
for use with desktop Liquid Crystal Display
(LCD) and industrial LCD panels typically ranging in size from 10.4-inches to 17-inches. This
two output inverter is the ideal solution to power
virtually any two lamp application.
Direct Drive Technology. The module design is based on a new patented1 Direct Drive
topology, which provides a number of cost and
performance advantages. The LXM1620-01
Direct Drive inverters eliminate the classic resonant inductor and capacitors, thus reducing cost
and allowing a substantial reduction in module
size.
Fixed-Frequency Operation. 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.
Fail-safe Feature For Multiple Lamp Applications. Our multi-output inverters are designed to keep your application operating at near
normal brightness in the event that a lamp fails.
A T A
S
H E E T
K E Y F E AT U R E S
This allows the display to remain "on-line" until
lamp replacement is convenient.
Dual Module Uses Standard Power
Supply. The LXM1620 module uses a standard
12V ±10% input supply. It also ensures nominal power consumption with 2 lamps requiring
only 8 watts. Lamp current is fully regulated
with respect to input voltage and output impedance variations.
Dimming Features. The LXM1620 modules are equipped with a dimming input that permits brightness control from an external potentiometer or DC voltage. In addition, the sleep
input reduces module power to a few microwatts
in shut down mode. All LXM1620 modules feature both output open and short-circuit protection.
The Most Efficient and
Cost-effective Backlight Inverter for Desktop/Industrial Applications. Linfinity's proprietary Direct Drive architecture is the highest
efficiency, small form factor solution for all
multiple lamp applications. The LXM1620 is
fully customizable (electronically and mechanically) to specific customer requirements.
1
D
US Patent Numbers: 5923129 & 5930121
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Drive Two Lamps With One Module
Small, Compact Size
High Efficiency
Multiple Outputs Provide Easy LCD
Connections
Low EMI And Noise
Low Power Sleep Mode
Output Short And Open Circuit Protection
3:1 Dimming Control
Adjustable Lamp Current Up To 6.0mA Per
Lamp
Long Lamp Life With Soft-Start And
Accurate Lamp Current Regulation
A P P L I C AT I O N S
■ Desktop LCD Monitors And Panels
■ Industrial LCD Panels
■ Hi-Brite Displays
BENEFITS
■ Cool Operation
■ Smooth, Easy-To-Use Brightness Control
■ Single 12 Volt Supply
NOTE: For current data & package dimensions, visit our web site: http://www.linfinity.com.
PRODUCT HIGHLIGHT
LXM1620 "U N I V E R S A L " M O D U L E C O N N E C T I O N O P T I O N S
Dual Connector Configuration
CCFL Lamp
CN3
CCFL Lamp
CN1
CN2
LXM1620-01
CN1
LXM1620-01
CN2
Single Connector Configuration
CCFL Lamps
CN3
Desktop Display
Desktop Display
M O D U L E O R D E R I N F O R M AT I O N
Part Number
Lamp Run Voltage
Lamp Current
LXM1620-01
Copyright © 2000
Rev. 0.9 10/00
LINFINITY
500 - 750VRMS
MICROELECTRONICS
6mA
INC.
11861 WESTERN AVENUE, GARDEN GROVE, CA. 92841, 714-898-8121, FAX: 714-893-2570
1
PRODUCT DATABOOK 1996/1997
LXM1620-01
D I R E C T D R I V E D U A L L A M P CCFL I N V E RT E R M O D U L E
P
D
R E L I M I N A R Y
A T A
S
H E E T
A B S O L U T E M A X I M U M R AT I N G S
(Note 1)
Input Supply Voltage (VIN) ............................................................................................................................................................ -0.3V to 18V
Output Voltage, no load ..................................................................................................................................... Internally Limited to 1800VRMS
Output Current .................................................................................................................................................. 10.0mARMS (Internally Limited)
Output Power (per Lamp) ........................................................................................................................................................................ 6.0W
Input Signal Voltage, (SLEEP and BRITE Inputs) .......................................................................................................................... -0.3V to VIN
Ambient Operating Temperature .................................................................................................................................................... 0°C to 70°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 the
specified terminal.
R E C O M M E N D E D O P E R A T I N G C O N D I T I O N S (R.C.)
Thismodulehasbeendesignedtooperateoverawiderangeofinputandoutputconditions. However,bestefficiencyandperformancewillbeobtainedifthemoduleisoperated
undertheconditionlistedinthe'R.C.'column. Min.andMax.columnsindicatevaluesbeyondwhichtheinverter,althoughoperational,willnotfunctionoptimally.
Parameter
Symbol
Input Supply Voltage Range (Functional)
Input Supply Voltage (Fully Regulated Lamp Current)
Output Power (per Lamp)
LXM1620-01
Brightness Control Input Voltage Range
Lamp Operating Voltage
LXM1620-01
Lamp Current (Full Brightness - per Lamp)
Operating Ambient Temperature Range
Recommended Operating Conditions
Min.
R.C.
Max.
VIN
10.2
10.2
PO
VBRT ADJ
VLAMP
0.0
500
IOLAMP
TA
0
Units
12
12
4
16
13.8
5
V
V
W
625
5.0
750
V
VRMS
70
mARMS
°C
6.0
ELECTRICAL CHARACTERISTICS
Unless otherwise specified, these specifications apply over the recommended operating conditions and 25°C ambient temperature for the LXM1620.
Parameter
Symbol
Test Conditions
LXM1620-xx
Min. Typ.
Max.
Units
5.4
mA RMS
Output Pin Characteristics
Full Bright Lamp Current
1620-01
I L (MAX)
VBRT ADJ = 5.0VDC, SLEEP = HIGH, VIN = 12VDC
IL (MIN)
VBRT ADJ = 0VDC, SLEEP = HIGH, VIN = 12VDC
6.0
6.6
(per Lamp)
Minimum Lamp Current (per Lamp)
(Note 2)
Lamp Start Voltage
Operating Frequency
VLS
fO
0°C < TA < 40°C, VIN ≥ 10.8VDC
VBRT ADJ = 5.0VDC, SLEEP = HIGH, VIN = 12VDC
IBRT
VC
VC
VBRT ADJ = 0VDC
IO (LAMP) = 100%
IO (LAMP) = Minimum
0.5
1500
52
57
mARMS
1800
62
VRMS
KHz
-10
µADC
VDC
VDC
VDC
VDC
µADC
µADC
BRITE Input
Input Current
Input Voltage for Max. Lamp Current
Input Voltage for Min. Lamp Current
-6
-8
5.0
0
SLEEP Input
RUN Mode
SLEEP Mode
Input Current
VSLEEP (HI)
VSLEEP (LO)
ISLEEP
SLEEP = 5.0V
2.2
-0.3
60
120
VIN
0.8
180
0
1
50
Power Characteristics
Sleep Current
IIN (MIN)
VIN = 12VDC , SLEEP = 0VDC
Note 2. Minimum lamp current required to maintain even light output may vary with display panel.
2
Copyright © 2000
Rev. 0.9 10/00
PRODUCT DATABOOK 1996/1997
LXM1620-01
D I R E C T D R I V E D U A L L A M P CCFL I N V E RT E R M O D U L E
P
R E L I M I N A R Y
D
A T A
S
H E E T
FUNCTIONAL PIN DESCRIPTION
Conn.
CN1
Pin
Description
CN1-1, 2
VIN
Input Power Supply. (10.2V≤ VIN ≤ 16V)
CN1-3, 4
GND
Power Supply Return.
CN1-5
SLEEP
ON/OFF Control. (2.2V < SLEEP < VIN = ON, -0.3V < SLEEP < 0.8V = OFF)
CN1-6
BRITE
Brightness Control (-0.3V to 5.0VDC). 5.0VDC gives maximum lamp current.
CN1-7, 8
N.C.
Leave unconnected.
CN2 and CN3: Refer to Figure 1
PHYSICAL DIMENSIONS
LXM1620-01
All dimensions are in inches (mm)
5.51 (140)
CN1
CN3
2.47 (62.75)
0.060
(1.52) max.
0.94
(24)
CN2
0.053
(13.45)
Ø 0.12 (3.0) Grounded Mounting Hole
0.370 (9.4)
max.
Warning!! High Voltage Present At All Output Connectors
0.449
(11.4) max.
0.307 (7.8)
Copyright © 2000
Rev. 0.9 10/00
3
PRODUCT DATABOOK 1996/1997
LXM1620-01
D I R E C T D R I V E D U A L L A M P CCFL I N V E RT E R M O D U L E
P
R E L I M I N A R Y
D
A T A
S
H E E T
C O N N E C T O R S C H E M AT I C
8
CN1
1
1
3
2
2
3
1
VHI1
CN3
VHI2
Inverter
Output 1
CN2
Inverter
Output 2
FIGURE 1 — LXM1620-01 Connector Schematic
Connectors:
CN1 = MOLEX 53261-0890
Mates With:
Pins: 50079-8100*, Housing: 51021-0800
CN2, CN3 = JST SM03(4.0)B-BHS-1-TB
JST BHR-03VS-1
* Loose (-8000, Chain) Recommended #26 AWG wiring
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 LXM1620-01 module connectors are wired per industry standard. The lamphot wires (high voltage wires) are always
on pin 1 or 2, and thecold wire (low voltage wire) is always on pin 3.
F A I L S A F E F E AT U R E F O R M U L T I P L E L A M P O P E R AT I O N S
Our multi-output inverters are designed to keep your application operating at near normal brightness in the event that a lamp fails. This allows
the display to remain "on-line" until lamp replacement is convenient.
Linfinity "pairs" the lamps so that if one lamp in the pair breaks, most
of its current is added to the good lamp. CCFLs will respond with more
brightness for a period of time. Operating time in this mode will be a
function of the lamps age but should be typically in the order of hundreds
of hours.
This operating characteristic can provide adequate display performance for a limited, but useful period of time. Shortening of the lamp life
in this mode is typically not a concern as it is recommended thatall lamps
in a display be replaced at the same time.
Lamps
IS
FIGURE 2 — Dual Output Stage
4
Copyright © 2000
Rev. 0.9 10/00
PRODUCT DATABOOK 1996/1997
LXM1620-01
D I R E C T D R I V E D U A L L A M P CCFL I N V E RT E R M O D U L E
P
R E L I M I N A R Y
D
A T A
S
H E E T
DIRECT DRIVE OUTPUT ARCHITECTURE
Direct Drive architecture includes two load feedback control loops to
provide uncompromised CCFL ignition and operation characteristics.
Lamp current is regulated in the CCFL return lead (ISNS loop) to insure
constant light output with changing lamp parameters and power supply
voltage. This also allows accurate and repeatable brightness control.
Dimming ratio with the LX1620 analog dimming inverters is typically 6:1
when driving dual LCD lamp panels.
If no current flows in the CCFL return path because of an unstruck or
failed lamp, the inverter applies full strike voltage potential. The output
voltage feedback loop (VSNS) takes control and regulates output voltage to
1650VRMS. This insures the lamp will ignite under worst case temperature
and aging conditions.
Because output voltage is actively regulated, it will never exceed
component and panel insulation ratings. This prevents destructive corona
discharge to insure long term reliability of the system.
High Voltage
Transformer
VHI1
SLEEP
Controller
GND
LAMP 1
BRITE
Transformer
Driver
VSENSE
ISENSE
VLO
FIGURE 3 — LXM1620 Block Diagram
(Only one lamp shown)
T Y P I C A L A P P L I C AT I O N S
5.0VDC
BRITE
VIN
VHI2
VHI1
0V
5V
Lamp 1
LXM1620-xx
SLEEP
GND
Lamp 2
£ 10k
10.8VDC- 16VDC
VLO
FIGURE 4 — Potentiometer Brightness Control
PRELIMINARY DATA - Information contained in this document is pre-production data, and is proprietary to LinFinity. It may not 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. 0.9 10/00
5