LXM1611-01

P ATENTS P TM ENDING L IN D O C # : 1611 RangeMAX T HE LXM1611-01 D ATA D I G I TA L D I M M I N G C C F L I N V E RT E R M O D U L E I NFINITE P OWER OF I N N O VAT I O N P RELIMINARY S HEET DESCRIPTION RangeMAX Wide Range Dimming, Single Output Inverter. The LXM1611 series of Direct DriveTM CCFL (Cold Cathode Fluorescent Lamp) Inverter Modules are specifically designed for driving LCD backlight lamps. Similar to the LXM1610, the LXM1611 excels in applications where critical parameters include very wide range dimmability, high efficiency and reliable fail-safe design in a small form factor. Unlike the LXM1610 or any traditional dimming CCFL inverters, the LXM1611 provides the designer a vastly superior display brightness range. 100:1+ brightness range is achievable with virtually any LCD display. 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"). The LXM1611 is recommended for use in panels with low-voltage insulation on the lamp return wire. RangeMAX Digital Dimming Technique. Digital dimming provides flickerfree brightness control in any wide-range dimming application. Dimming ratios greater than 100:1 can be achieved. 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 "How RangeMAX Works" Section) Wide Input Voltage Range. The modules convert unregulated DC voltage from the system battery or AC adapter directly to highfrequency, high-voltage waves required to ignite and operate CCFL lamps. Direct Drive Technology. The module design is based on a new Direct Drive topology, which provides a number of cost and performance advantages. The LXM1611-01 series Direct Drive inverters eliminate the classic resonant inductor and capacitors, thus reducing cost and allowing a 30% reduction in module size. Additional Features. 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. All LXM1611 modules feature both open and shorted lamp protection. The LXM1611 is fully customizable (electronically and mechanically) to specific customer requirements. s s s s s s K E Y F E AT U R E S RangeMAX Wide Range Dimming 8V to 18V Input Voltage Range 30% Smaller Than CS-ZVS Models Easy To Use Brightness Control MicroAmp SLEEP Mode Output Short-Circuit Protection And Automatic Strike-Voltage Regulation s 7.3mm Max. Module Height, 16mm Module Width s Fixed Frequency Operation A P P L I C AT I O N S s s s s Notebook And Sub-Notebook Computers Portable Instrumentation Desktop Displays Low Ambient Light Conditions (i.e. Aircraft Cabins, Automobile) BENEFITS s High Efficiency And Sleep Mode Feature Extends Computer Battery Life s Smooth, Flicker Free 1-100% Full-Range Brightness Control Gives Your Product A High Quality Image s Output Open Circuit Voltage Regulation Minimizes Corona Discharge For Long Life And High Reliability s Power Efficient, "Low Brightness" Capability Allows For Advanced Power Management NOTE: For current data & package dimensions, visit our web site: http://www.linfinity.com. PRODUCT HIGHLIGHT RANGEMAX 5 VS. ANALOG DIMMING s RangeMAX technology allows the designer to operate in a lower "brightness" and therefore at lower "power consumption" than can be reached using traditional analog dimming inverters. s Dotted line indicates area where panel variations and parasitics will impact minimum light level with analog dimming. s Data presented for a RangeMAX inverter driving a 13.3" LCD with a 1.2 Nit to 120 Nit brightness range. The minimum power levels were 0.4 watts (RangeMAX) vs. 2.1 watts (analog dimming) for a power consumption savings of 1.7 watts. Power Used (Watts) Standard Analog Dimming Inverter 4 3 2 1 LinFinity's RangeMAX 0 30 45 60 75 90 105 Light Output (Nits) M O D U L E O R D E R I N F O R M AT I O N LXM1611-01 Copyright © 1999 Rev. 0.4 8/99 LINFINITY MICROELECTRONICS INC. 11861 WESTERN AVENUE, GARDEN GROVE, CA. 92841, 714-898-8121, FAX: 714-893-2570 1 P AT E N T P E N D I N G PRODUCT DATABOOK 1996/1997 LXM1611-01 D I G I TA L D I M M I N G C C F L I N V E RT E R M O D U L E P RELIMINARY RangeMAX D ATA TM 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) ........................................................................................................................................................ -0.3V to 18V Output Voltage, no load .............................................................................................................................. Internally Limited to 1800VRMS Output Current ............................................................................................................................................. 10.0mARMS (Internally Limited) Output Power ........................................................................................................................................................................................ 6.0W Input Signal Voltage (BRITE Input) ....................................................................................................................................... -0.3V to 6.5V Input Signal Voltage (SLEEP, VSYNC(-), VSYNC(+) 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.) 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 Brightness Control Input Voltage Range Lamp Operating Voltage Lamp Current (Full Brightness) Operating Ambient Temperature Range Symbol VIN PO VBRT ADJ VLAMP IOLAMP TA Recommended Operating Conditions Min. R.C. Max. 8 9 0.0 300 0 12 12 4 675 7.0 18 16 5 2.5 800 70 Units V V W V VRMS mARMS °C ELECTRICAL CHARACTERISTICS Unless otherwise specified, these specifications apply over the recommended operating conditions and 25°C ambient temperature for the LXM1611. Parameter Output Pin Characteristics Full Bright Lamp Current Minimum Lamp Current (Note 2) Lamp Start Voltage Operating Frequency Symbol Test Conditions LXM1611-01 Min. Typ. Max. 6.3 1500 52 -10 7.0 0.14 57 -12 2.5 0 7.7 1800 62 -14 2.6 0 VIN 0.8 180 6.5 1.0 75 250 150 50 Units IL (MAX) IL (MIN) VLS fO IBRT VC VC VSLEEP (HI) VSLEEP (LO) ISLEEP VSYNCH (HI) VSYNCH (LO) ZIN tPW fSYNC IIN (MIN) VBRT ADJ = 2.5VDC, SLEEP = HIGH, Burst Duty = 100%, VIN = 9VDC VBRT ADJ = 0VDC, SLEEP = HIGH, Burst Duty = 2%, VIN = 9VDC 0°C < TA < 40°C, VIN ≥ 7.0VDC VBRT ADJ = 2.5VDC, SLEEP = HIGH, VIN = 12VDC VBRT ADJ = 0VDC IO (LAMP) = 100% Duty Cycle IO (LAMP) = Minimum Duty Cycle mARMS mA RMS VRMS KHz µADC VDC VDC VDC VDC µADC VDC VDC kΩ µs Hz µADC BRITE Input Input Current Input Voltage for Max. Lamp Current Input Voltage for Min. Lamp Current SLEEP Input RUN Mode SLEEP Mode Input Current 2.2 -0.3 SLEEP = 5.0V 4.0 -0.3 60 25 49 VIN = 15VDC , SLEEP ≤ 0.8V 120 VSYNC(-) / VSYNC(+) Characteristics Logic High Level Logic Low Level Input Impedance Pulse Width (Note 3) Input Frequency 66 Power Characteristics Sleep Current 10 Note 2. Minimum lamp current required to maintain even light output may vary with display panel. 3. The module will be functional with pulse widths much larger than 250µs, but will have limited dimming. 2 Copyright © 1999 Rev. 0.4 8/99 PRODUCT DATABOOK 1996/1997 PATENT PENDING RangeMAX TM LXM1611-01 D I G I TA L D I M M I N G C C F L I N V E RT E R M O D U L E P RELIMINARY D ATA S HEET FUNCTIONAL PIN DESCRIPTION Conn. CN1 CN1-1 CN1-2 CN1-3 CN1-4 CN1-5 CN1-6 CN1-7 CN1-8 Pin Description VIN GND SLEEP BRITE VSYNC(-) VSYNC(+) Input Power Supply. (8V ≤ VIN ≤ 18V) Power Supply Return. ON/OFF Control. (2.2V < SLEEP < VIN = ON, -0.3V < SLEEP < 0.8V = OFF) Brightness Control (-0.3 to 2.5VDC). 2.5VDC gives maximum lamp current. Vertical syncronization input, negative going. Vertical syncronization input, positive going. } 25µs < tPW < 250µs, 49Hz < fSYNC < 150Hz CN2 CN2-1 CN2-2 VHI VLO High voltage connection to high side of lamp. Connect to lamp terminal with shortest lead length. DO NOT connect to ground. Connection to low side of lamp. Connect to lamp terminal with longer lead length. DO NOT connect to Ground. PHYSICAL DIMENSIONS LXM1611-01 All dimensions are in inches (mm). 3.93 (100) 2.36 (60) 2.06 (52.25) 1.20 (30.5) CN2 CN1 Ø 0.116 (2.95) Grounded Mounting Hole 0.15 (3.85) 0.64 (16) 0.287 Max. (7.3) Warning!! High Voltage Present 0.031 (0.79) max. Connectors: CN-1 = MOLEX 53261-0890 CN-2 = JST SM02(8.0) B-BHS-TB Recommended Mate: Pins: 50079-8100*, Housing: 51021-0800 * Loose (-8000, Chain) Recommended #26 AWG wiring Pins: 5BH-001T-P0.5, Housing: BHR-03VS-1 Copyright © 1999 Rev. 0.4 8/99 3 P AT E N T P E N D I N G PRODUCT DATABOOK 1996/1997 LXM1611-01 D I G I TA L D I M M I N G C C F L I N V E RT E R M O D U L E P RELIMINARY RangeMAX D ATA TM S HEET HOW RANGEMAX WORKS LAMP VOLTAGE & LAMP CURRENT — Burst Mode Operation (770VRMS) (760VRMS) (7.6mARMS) (6.7mARMS) FIGURE 1 — 50% Burst Duty Cycle FIGURE 2 — 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 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. (760VRMS) (6.7mARMS) FIGURE 3 — 2% Burst Duty Cycle (Expanded Time Base) VBRITE 0-2.5V DC Ramp Comparator Transformer Driver High Voltage Transformer VHI Ramp Gen. VSYNC(-) VSYNC(+) ISENSE VSENSE VLO FIGURE 4 — RangeMAX Block Diagram LAMP 4 Copyright © 1999 Rev. 0.4 8/99 PRODUCT DATABOOK 1996/1997 PATENT PENDING RangeMAX TM LXM1611-01 D I G I TA L D I M M I N G C C F L I N V E RT E R M O D U L E P RELIMINARY D ATA S HEET H O W R A N G E M A X W O R K S (continued) HIGHLIGHTS s On-board 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. s An on-board oscillator operates the inverter BURST rate above 95Hz, well beyond standard 50/60Hz video refresh rates where the eye can perceive pulsing light. s 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. s 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 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. s Separate inputs are provided for negative and positive vertical sync pulses so external inversion is not needed. s 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. T Y P I C A L A P P L I C AT I O N 2.5VDC 9-18VDC £ 10k BRITE VIN VHI CCFL TUBE VLO LXM1611-01 0V 5V SLEEP VSYNC(-) VSYNC(-) VSYNC(+) VSYNC(+) GND FIGURE 5 — Potentiometer Brightness Control PWM Signal from System P.W. £ 100µs 4.99k 4.7µF 4.99k* BRITE s The brightness control may be a simple 10k potentiometer or a voltage output DAC. A PWM signal from a micro-controller may also be used with a suitable filter such as shown in Figure 5A. s If synchronization to the video framerate is desired, connect the vertical sync pulse from the system video controller to the appropriate VSYNC input. If the pulse is negative going ( ), connect it to VSYNC(-). If ), connect it to VSYNC(+). positive going ( If no video synchronization is desired, leave both VSYNC(-) and VSYNC(+) floating. s 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. s Connect VHI t o 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. RangeMAX INVERTERS LXM1611-01 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 amplitude. FIGURE 5A — PWM Brightness Control Also available in Dual Output LXM1621-01 and Quad Output LXM1641-01 versions for multiple lamp applications. RangeMAX and Direct Drive are trademarks of Linfinity Microelectronics Inc. 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 © 1999 Rev. 0.4 8/99 5