View LXM1653-01_1268790.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

P
ATENT
P
ENDING
LIN D O C #: 1653
LXM1653-01
FLOATING OUTPUT DRIVE, CCFL INVERTER MODULES
T
HE
I
NFINITE
P
OWER
OF
I
N N O VAT I O N
P
RELIMINARY
D
ATA
S
HEET
DESCRIPTION The LXM1653 floating output drive CCFL (Cold Cathode Fluorescent Lamp) Inverter Module is specifically designed to drive large LCD displays (11.3" and larger), which are used in notebook computers. This new inverter was specifically designed to reduce the leakage currents from the lamp to the reflector or the metal frame of the panels. The floating output architecture of this inverter also permits a much wider dimming range when compared to non-floating designs, and allows an additional 10% efficiency improvement. The module converts unregulated DC voltage from the system battery or AC adapter directly to high-frequency, high-voltage sine waves required to ignite and operate CCFL lamps. The module design is based on a proprietary Linfinity IC that provides important new performance advances. Remarkable improvements in efficiency and RF emissions result from this single stage resonant inverter, featuring a patented Current Synchronous, Zero Voltage Switching (CS-ZVS) topology. CS-ZVS produces nearly pure sine wave currents in the lamp, enabling maximum light delivery, while reducing both conducted and radiated noise. This topology simultaneously performs two tasks including line voltage regulation and lamp dimming through lamp current regulation. These two functions are performed in a single power stage made up of a pair of low-loss MOSFETs. The MOSFETs drive a low current resonant circuit that feeds the primary of a high-voltage transformer with a sinusoidal voltage. Required L and C values in the resonant circuit are such that very lowloss components can be used to obtain higher electrical efficiency than is possible with previous topologies. The full-bridge LXM1653 provides peak efficiency when operated at input voltages from 6.5 volts to 18 volts. In addition, this module is equipped with a dimming input that permits full range brightness control from an external potentiometer or PWM signal, and a sleep input that reduces module power to a few microwatts in shutdown mode. Output open and short circuit protection are also featured on this module.
K E Y F E AT U R E S
s FULLY FLOATING OUTPUT s 35% MORE LIGHT OUTPUT AT 5 WATTS s GREATER EFFICIENCY THAN GROUNDED OUTPUT DESIGNS s 6.5V TO 18V INPUT VOLTAGE RANGE s VERSATILE BRIGHTNESS CONTROL INPUT s 10 MICROAMP SLEEP CURRENT s OUTPUT SHORT CIRCUIT PROTECTION AND AUTOMATIC OVER VOLTAGE LIMITING s 7.4mm MAX HEIGHT, NARROW FOOTPRINT s MINIMIZE THERMOMETER EFFECTS s MINIMIZE LAMP TO PANEL LEAKAGE CURRENT
A P P L I C AT I O N S
s 11.3" LCD PANELS AND LARGER s NOTEBOOK AND SUB-NOTEBOOK COMPUTERS s PORTABLE INSTRUMENTATION s AUTOMOTIVE DISPLAYS s DESKTOP DISPLAYS s AIRLINE ENTERTAINMENT CENTERS
BENEFITS
s ULTRA-HIGH EFFICIENCY, LINE VOLTAGE REGULATION AND SLEEP MODE EXTEND COMPUTER BATTERY LIFE s COOL OPERATION PERMITS CLOSE PROXIMITY TO LCD PANEL WITHOUT DISPLAY DISTORTION s SMOOTH, FULL-RANGE BRIGHTNESS CONTROL GIVES YOUR PRODUCT A HIGH QUALITY IMAGE s LOW EMI / RFI DESIGN MINIMIZES SHIELDING REQUIREMENTS s NARROW, LOW-PROFILE MODULE FITS INTO MOST LCD ENCLOSURES
PRODUCT HIGHLIGHT
F L O A T I N G OUTPUT A R C H I T E C T U R E
High Voltage Transformer
CS-ZVS Inverter
DC VIN
MODULE
ORDER
CCFL
INFO
FULL-BRIDGE DRIVE LXM1653-01
F O R F U R T H E R I N F O R M AT I O N C A L L ( 7 1 4 ) 8 9 8 - 8 1 2 1
Copyright (c) 1997 Rev. 0.1 3/97
11861 WESTERN AVENUE, GARDEN GROVE, CA. 92841
1
P AT E N T P E N D I N G
PRODUCT DATABOOK 1996/1997
LXM1653-01
FLOATING OUTPUT D RIV E , CCFL INVERTER MODULES
P
RELIMINARY
D
ATA
S
HEET
(Note 1)
A B S O L U T E M A X I M U M R AT I N G S
Input Supply Voltage (VIN)......................................................................................................................................................... 6.5V to 18V Output Voltage, no load .............................................................................................................................. Internally Limited to 2000VRMS Output Current .............................................................................................................................................. 7.5mARMS (Internally Limited) Output Power ........................................................................................................................................................................................... 6W Input Signal Voltage, (SLEEP and BRITE Inputs) .................................................................................................................. -0.3V to 6.5V Ambient Operating Temperature, zero airflow ........................................................................................................................ 0C to 60C 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 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.) 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 Output Power Brightness Control Input Voltage Range Lamp Operating Voltage Lamp Current - Full Brightness Operating Ambient Temperature Range
Symbol
Recommended Operating Conditions Min. R.C. Max.
6.5 4.0 0.0 300 0 600 7.2 18 6.0 2.0 800 60
Units
V W V VRMS mA RMS C
PO VBRITE VLAMP IOLAMP TA
ELECTRICAL CHARACTERISTICS
Unless otherwise specified, these specifications apply over the recommended operating conditions and 25C ambient temperature for the LXM1653.
Parameter Output Pin Characteristics
Full Bright Lamp Current
Symbol
Test Conditions
VBRITE = 2.0 VDC , VLAMP = 750VRMS, VIN 10.8VDC VBRITE = 2.0 VDC , VLAMP = 750VRMS, VIN 9.0VDC VBRITE = 2.0 VDC , VLAMP = 350VRMS, VIN 6.5VDC VBRITE = 2.0 VDC , VLAMP = 600VRMS, VIN 8.0VDC VBRITE = 0.0 V DC 0C < TA < 60C VBRITE = 2.5VDC, SLEEP = Logic High, VIN = 12V VBRITE = 0V DC IO (LAMP) = 100% IO (LAMP) = 50%
Min.
6.8 5.0 6.8 6.8 1800 55
LXM1653 Typ. Max.
7.2 5.5 7.2 7.2 2.5 60 -200 2.5 1.25 7.7
Units
IL (MAX)
Minimum Lamp Current Lamp Start Voltage Operating Frequency
IL (MIN) VLS fO IBRITE VC VC VIH VIL IIN V REF IREF IIN (MIN)
65 -1000 2.6
mA mA mA mA mA RMS VRMS KHz nADC VDC VDC VDC VDC ADC VDC ADC ADC
Brightness Control
Input Current Input Voltage for Max. Lamp Current Input Voltage for 50% Lamp Current 2.4
SLEEP Input
Input Logic 1 Input Logc 0 Input Current 2.5 0 VSLEEP = 0 - 5VDC 0 < IREF < 500A 2.40 500 50 2.50 5.5 0.8 100 2.60
Voltage Reference
Output Voltage Output Current
Power Characteristics
Sleep Current VIN = 12V, SLEEP = Logic 0 10 30
2
Copyright (c) 1997 Rev. 0.1 3/97
PRODUCT DATABOOK 1996/1997
P AT E N T P E N D I N G
LXM1653-01
FLOATING OUTPUT DRIVE, CCFL INVERTER MODULES
P
RELIMINARY
D
ATA
S
HEET
FUNCTIONAL PIN DESCRIPTION
Conn. CN1
CN1-1 CN1-2 CN1-3 CN1-4 CN1-5
Pin
Description
VIN GND SLEEP
Input voltage. (+6.5 to +18VDC ) Power supply return. Logical high on this pin enables inverter operation. Logical low removes power from the module and the lamp. A floating input is sensed as a logical low and will disable inverter operation. If not used, connect SLEEP to VIN. Brightness control input. Apply 0.0 to 2.0 volts DC to control lamp brightness. Lamp current varies linearly with input voltage. Open circuit or 2.0V gives maximum brightness. This input may also be driven with a PWM logic signal. See Application Notes Section. Brightness control signal return. For best results do not run VIN power supply return current through this pin. Reference Voltage Output. 2.5V @ 500A max. For use with external dimming circuit.
CN1-6
BRITE
CN1-7 CN1-8
AGND VREF
CN2
CN2-1 CN2-2 LAMP HI LAMP LO High-voltage connection to high side of lamp. Connect to lamp terminal with shortest lead length. Do not connect to ground. High-voltage connection to low side of lamp. Connect to lamp terminal with longer lead length. This lead may be safely connected to ground, but may not result in specified performance depending on system wiring and lamp characteristics.
A P P L I C AT I O N D I A G R A M
9.0 8.0
MS MS MS
ILAMP - (mARMS)
=6 00V R
=6 50V R
=7 00V R
AM P
VL
AM P
VL
5.0 4.0 3.0 6 7 8 9 10 18
VIN - (Volts DC)
FIGURE 1 -- MAXIMUM LAMP CURRENT vs. INPUT VOLTAGE FOR TYPICAL LAMP VOLTAGES
Copyright (c) 1997 Rev. 0.1 3/97
VL
V
LA MP
AM P
6.0
350 VR
=7 60 V
7.0
MS
RM S
3
P AT E N T P E N D I N G
PRODUCT DATABOOK 1996/1997
LXM1653-01
FLOATING OUTPUT D RIV E , CCFL INVERTER MODULES
P
RELIMINARY
D
ATA
S
HEET
T Y P I C A L A P P L I C AT I O N S
AC/DC Adapter
R2, 25k R1 100k
3.3 or 5V From Power Management Logic
VREF BRITE
VIN LAMP HI CFL TUBE Inside LCD Panel
Sytem Battery (NiCd, NiMH, etc.)
LXM1653
SLEEP AGND LAMP LO GND
CMOS or TTL
FIGURE 21 -- NOTEBOOK SYSTEM APPLICATION
12VDC 2.0VDC 1K TO 100K VIN BRITE LAMP HI CCFL TUBE LAMP LO GND
LXM1653
ON / OFF
SLEEP
FIGURE 22 -- POTENTIOMETER BRIGHTNESS CONTROL
+5V S1 "Increase" From Logic (optional)
N.O.
+5V
U1
47k
N.O.
UC D
RH RW RL
R1
VREF BRITE AGND
* S1 & S2 are momentary push buttons, normally open contacts. * U1 = 100k digital pot. * R1 value optional for choosing dimming range.
S2 "Decrease" 47k +5V
DC
LXM1653
FIGURE 23 -- NONVOLATILE DIGITAL BRIGHTNESS CONTROL
4
Copyright (c) 1997 Rev. 0.1 3/97
PRODUCT DATABOOK 1996/1997
P AT E N T P E N D I N G
LXM1653-01
FLOATING OUTPUT DRIVE, CCFL INVERTER MODULES
P
RELIMINARY
D
ATA
S
HEET
T Y P I C A L A P P L I C AT I O N S
12VDC VIN PWM BRITE
(continued)
LAMP HI CCFL TUBE LAMP LO
LXM1653
ON / OFF
SLEEP
GND
PWM
Period
PULSE WIDTH 10sec Period 100sec 0 Pulse Width Period
FIGURE 24 -- PWM BRIGHTNESS CONTROL
Copyright (c) 1997 Rev. 0.1 3/97
5
P AT E N T P E N D I N G
PRODUCT DATABOOK 1996/1997
LXM1653-01
FLOATING OUTPUT D RIV E , CCFL INVERTER MODULES
P
RELIMINARY
D
ATA
S
HEET
PHYSICAL DIMENSIONS
LXM1653
5.35 (136)
Conn Entry
5.256 (133.5) 1-1
.089 (2.25)
CN-1
1
1
CN-2
L1
T1
0.512 (13.0) .256 (6.5)
.089 (2.25)
O 0.089 (2.26) Dia. Mtg. Hole 2 Plcs
2-1
Conn Entry
0.291 (7.40) Max.
Warning!! High Voltage Present
0.060 (1.52) All dimensions in inches (mm)
CN-1 = MOLEX P/N: 53261-0890 CN-2 = JST P/N: SM02-(8.0)B-BHS-1D
6
Copyright (c) 1997 Rev. 0.1 3/97

▲Up To Search▲

Price & Availability of LXM1653-01

	To Download LXM1653-01 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .