Not Recommended For New Design LX1686 I N T E G R A T E D Digital Dimming CCFL Controller IC P R O D U C T S P RODUCTION D ATA KEY FEATURES DESCRIPTION RangeMAX™ Wide Range Dimming (>100:1) Synchronizable to Display Video Frequency High Voltage Feedback Loop Directly Controls Maximum Open Lamp Micro-Amp Sleep Mode User Programmable Fixed Frequency Operation Under-Voltage Lockout Feature With Power-Up Reset Built-In Soft-Start Feature Operates With 3.3V or 5V power Supplies 100mA Output Drive Capability bs ol et e Safety and reliability features include a new dual feedback control loop that permits regulation of maximum lamp strike voltage as well as lamp current. Regulating maximum lamp voltage permits the designer to provide for ample worst case lamp strike voltage while at the same time conservatively limit maximum open circuit voltage. An innovative new strike voltage generation technique enables the nodule designer to optimize high voltage transformer design for maximum operating efficiency with no power dissipating overhead to guarantee strike capability Direct drive topology is a nonresonant, oscillator-controlled PWM regulation method. The LX1686 allows a wide choice of fixed operating frequencies to match lamp current frequency to the lamp’s most efficient operating point, and to minimize high frequency interference. APPLICATIONS Notebooks Instrumentation Display Desktop Computer Monitors Low Ambient Light Displays (used in Aircraft, Automobiles, and Hand-Held Equipment) IMPORTANT: For the most current data, consult MICROSEMI’s website: Protected by U.S. Patents 5,615,093; 5,923,129; 5,930,121; 6,198,234; Patents Pending Standard Analog Dimming Inverter 3 2 Microsemi's RangeMAX Light emitted by a CCFL is proportional to the current flowing through it. There are two ways to control the current: by adjusting the amplitude of a continuous AC current; or, as with RangeMAX technology, by varying the amount of time a burst of full current is present. RangeMAX technology frees the backlight inverter module designer to operate in a lower brightness and lower power consumption mode than is possible with conventional amplitude control methods. 1 0 0 30 45 60 75 90 105 LX1686 O Power Used (Watts) 4 BENEFITS Extremely High Efficiency From 3.3V to 5V Power Supplies Lower Cost Than Conventional Buck / Royer Inverter Topologies Improved Lamp Strike Capability Improved Over-Voltage Control PRODUCT HIGHLIGHT 5 Light Output (Nits) PACKAGE ORDER INFO TA (°C) PW Plastic TSSOP 24-PIN RoHS Complaint / Pb-free Transition D/C: 0442 0 to 85 -40 to 85 LX1686CPW LX1686IPW Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX1686CPW-TR) Copyright © 2000 Rev. 1.2a, 2005-01-27 WWW . Microsemi .C OM The LX1686 Backlight Controller IC provides all the control functions needed to implement Microsemi’s direct drive inverters used to operate cold cathode fluorescent lamps (CCFL’s). This IC can be used to control single or multiple-lamp configurations. CCFL’s are used for back or edge lighting of liquid crystal flat panel displays (LCD’s) and typically find application in notebook computers, web browsers, automotive and industrial instrumentation, and entertainment systems. The LX1686 includes a PWM controlled lamp current burst circuit that can provide a > 100:1 dimming range from a simple zero to 2.5V potentiometer input. The PWM dimming burst rate is easily synchronized to the LCD panel’s frame rate to prevent interference from optical beat frequencies. SHEET Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 1 Not Recommended For New Design LX1686 I N T E G R A T E D P R O D U C T S Digital Dimming CCFL Controller IC P RODUCTION D ATA ABSOLUTE MAXIMUM RATINGS SHEET PACKAGE PIN OUT 1 24 2 23 3 22 4 21 5 20 6 19 7 18 8 17 9 16 10 15 11 14 12 13 BOUT VDD_P VDD TRI_C OLSNS ISNS ICOMP VSNS VCOMP BRT I_R ENABLE bs ol et e AOUT VSS_P VSS AFD_C RAMP_C RAMP_R FVERT PD_CR VCO_C BRT_POS BRITE DIG_DIM PW PACKAGE Note: 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 (Top View) WWW . Microsemi .C OM Supply Voltage (VDD, VDD_P) .................................................................................. 6.5V Digital Inputs ........................................................................................ -0.3 to VDD +0.5V Analog Inputs........................................................................................ -0.3 to VDD +0.5V Digital Outputs...................................................................................... -0.3 to VDD +0.5V Analog Outputs ..................................................................................... -0.3 to VDD +0.5V Operating Junction Temperature ...............................................................................150°C Storage Temperature ................................................................................... -65°C to 150°C RoHS / Pb-free Peak Package Solder Reflow Temperature (40 second maximum exposure).....................................................................260°C (+0,-5) RoHS / Pb-free 100% Matte Tin Lead Finish THERMAL DATA PW PACKAGE THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA 100°C/W Copyright © 2000 Rev. 1.2a, 2005-01-27 PACKAGE DATA O Junction Temperature Calculation: TJ = TA + (PD x θJA). The θJA numbers are guidelines for the thermal performance of the device/pc-board system. All of the above assume no ambient airflow. Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 2 Not Recommended For New Design LX1686 I N T E G R A T E D P R O D U C T S Digital Dimming CCFL Controller IC P RODUCTION D ATA SHEET FUNCTIONAL PIN DESCRIPTION DESCRIPTION AOUT Output driver A. VSS_P Power ground for output drivers only. AFD_C RAMP_C RAMP_R FVERT PD_CR VCO_C BRT_POS BRITE DIG_DIM ENABLE I_R BRT VCOMP VSNS Connects to an external capacitor, CAFD. Forcing to ground or VDD will make the VCO oscillate at approximately 50% of the maximum VCO frequency. Forcing to VDD/2 will make the VCO oscillate at 2x the FVERT frequency. Connects to external capacitor CRAMP for setting Direct Drive PWM operating frequency. Connects to external resistor RRAMP for setting Direct Drive PWM operating frequency. Vertical frequency reference digital input. Has internal pull down. Phase Detector Filter. Part of phase lock loop. Connects to external capacitor and resistor network. Connects to external capacitor CVCO Brightness control polarity. Has internal pull up. Leave open or pull up to VDD for dimming brightness proportional to BRITE voltage, connect to ground for brightness inversely proportional to BRITE voltage. Analog voltage input for brightness control. Digital Dimming Enable internal pull up. Leave open or pull up to VDD for operating in digital dimming mode. Connect to ground for analog dimming mode. Chip Enable internal pull up. High enables the chip. Low disables. Current Reference Resistor. External resistor to ground (Ri) determines internal capacitor CICOMP. Current Error Amplifier non-inverting input Voltage Error Amplifier output. Connects to external frequency compensation capacitor CVCOMP. Controls softstart timing. Voltage Error Amplifier inverting input. Current Error Amplifier output. Connects to external frequency compensation capacitor CICOMP. O ICOMP Signal ground. bs ol et e VSS ISNS Current Error Amplifier inverting Input. Open Lamp Sense Input. TRI_C Connects to external capacitor CTRI for setting strike Frequency ramp slope. PACKAGE DATA OLSNS VDD WWW . Microsemi .C OM PIN NAME VDD VDD_P Dedicated VDD for output buffers only. BOUT Output Driver B. Copyright © 2000 Rev. 1.2a, 2005-01-27 Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 3 Not Recommended For New Design LX1686 I N T E G R A T E D P R O D U C T S Digital Dimming CCFL Controller IC P RODUCTION D ATA SHEET Unless otherwise specified, the following specifications apply over the operating ambient temperature -0°C ≤ TA ≤ 85°C for the LX1686CPW and -40°C ≤ TA ≤ 85°C for the LX1686IPW except where otherwise noted. Test conditions: VDD = VDD_P = 3.0 to 5.5V, Ri = 40kΩ, CVCO = 0.01µF, CAFD = 0.22µF, CTRI = 0.83µF, CRAMP = 208pF, RRAMP = 15kΩ, CPD = 0.22µF, CPDB = 0.047µF, RPD = 110kΩ Parameter ` VDD IDD VDD_P IDD_P VTH_UVLO VH_UVLO VDD = VDD_P VDD = VDD_P = 5V VDD = VDD_P Volsns = VDD = VDD_P = 5V, CA = CB = 1000pF DIRECT DRIVE RAMP BLOCK Triangular Wave Generator Analog VP_TRI Output Peak Voltage Triangular Wave Generator Analog VV_TRI Output Valley Voltage Triangular Wave Generator Oscillation F_TRI Frequency Triangular Wave Generator Oscillation ICHG_TRI Charge Current Triangular Wave Generator Oscillation IDISCHG_TRI Discharge Current Ramp Generator Analog Output Peak VP_RAMP Voltage Ramp Generator Analog Output Valley VV_RAMP Voltage Ramp Frequency Change Threshold Ramp Generator Oscillation Frequency – Nominal Ramp Generator Oscillation Frequency – Maximum OLSNS Threshold Voltage OLSNS Hysteresis OLSNS-to-ICOMP Propagation Delay Min LX1686 Typ 3 Max 160 V mA V mA V mV 2.25 V 0.75 V 10 Hz 5 5.5 7 5.5 10 2.9 Auto-Frequency Detection Response BRITE Voltage Range Full-Brightness Brite Input Voltage Full-Darkness Brite Input Voltage Copyright © 2000 Rev. 1.2a, 2005-01-27 Units 3 2 2.7 Tri_c = 0V -2.3 -2.55 -2.9 µA Tri_c = 3V 2.3 2.65 2.9 µA 2.25 V 0.75 V VTH_RAMP_R VDD = 3V VDD = 5.5V 1.35 1.55 1.5 1.65 1.65 1.85 V V FRAMP VTRI_C = 1.4V 84 100 116 KHz FRAMP_HI VTRI_C = 2.25V 170 200 256 KHz VTH_OLSNS VH_OLSNS TD_OLSNS VDD = 3V VDD = 3V GBD 200 300 45 1 400 mV mV µS 200 Hz 45 FR_FVERT VTH_FVERT RFVERT VP_VCO VV_VCO FR_VCO_I_SRC FX_VCO TD_AFD Design Reference Only Design Reference Only VPD_CR = 3V, VDD = 3V AFC_C = 0V, CVCO = 0.01µF -6.4 FVERT Frequency is 200Hz, VDD = 3V VR_BRITE VBRITE_FULL VBRT_POS = VDD or float; BRITE = 2.5V VBRT_POS = 0V, BRITE = 0.5V VBRITE_DARK VBRT_POS = VDD or float, BRITE = 0.5V VBRT_POS = 0V, BRITE = 2.5V VDD/2 50 2.5 0.65 -5.8 250 -5.2 1000 0 2.35 2.35 0.35 0.35 Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 2.5 2.5 0.5 0.5 V kΩ V V µA Hz ms VDD 2.65 2.65 0.65 0.65 V V V V V Page 4 ELECTRICALS DIGITAL DIMMER BLOCK FVERT Input Frequency Capture Range FVERT Logic Threshold FVERT Input Resistance VCO Analog Output Peak Voltage VCO Analog Output Valley Voltage VCO Forced Source Current Forced VCO Oscillation Frequency O ` Test Conditions bs ol et e Power Supply Voltage Operating Current Power Supply Voltage Output Buffer Operating Current UVLO Threshold UVLO Hysteresis Symbol WWW . Microsemi .C OM ELECTRICAL CHARACTERISTICS Not Recommended For New Design LX1686 I N T E G R A T E D Digital Dimming CCFL Controller IC P R O D U C T S P RODUCTION D ATA SHEET Unless otherwise specified, the following specifications apply over the operating ambient temperature -0°C ≤ TA ≤ 85°C for the LX1686CPW and -40°C ≤ TA ≤ 85°C for the LX1686IPW except where otherwise noted. Test conditions: VDD = VDD_P = 3.0 to 5.5V, Ri = 40kΩ, CVCO = 0.01µF, CAFD = 0.22µF, CTRI = 0.83µF, CRAMP = 208pF, RRAMP = 15kΩ, CPD = 0.22µF, CPDB = 0.047µF, RPD = 110kΩ Parameter ` LX1686 Typ Max Units TD_BRITE 300 VDD/2 VDD/2 ns V V DIRECT DRIVE PWM BLOCK ISNS Threshold Voltage Range VAMP Transconductance VAMP Output Source Current VAMP Output Sink Current VAMP Output Voltage Range VSNS Threshold Voltage VCOMP Discharge Current IAMP Transconductance IAMP Output Source Current IAMP Output Sink Current IAMP Output Voltage Range VCMP Input Offset Voltage VCOMP-to-Output Propagation Delay ICMP Input Offset Voltage ICOMP-to-Output Propagation Delay ` Min DIGITAL DIMMING BLOCK (CONTINUED) BRITE-to-ICOMP Propagation Delay BRITE_POS Logic Threshold DIG-DIM Logic Threshold ` Test Conditions bs ol et e ` Symbol WWW . Microsemi .C OM ELECTRICAL CHARACTERISTICS VR_ISNS GM_VAMP IS_VAMP ISK_VAMP VR_VAMP VTH_VSNS ID_VCOMP GM_IAMP IS_IAMP ISK_IAMP VR_IAMP VOS_VCMP TD_VCOMP VOS_ICMP TD_ICOMP DIG_DIM = VDD VCOMP = 1.25V VCOMP = 1.5V VCOMP = 1.5V VCOMP = VSNS VCOMP = 0.5V, VDD = 3V BRITE = 0.5 – 2.6V ICOMP = 1.5V, VDD = 3V ICOMP = 1.5V, VDD = 3V VCOMP = 1.25V, VDD = 3V VDD = 3V ICOMP = 0.5 to 2.25V, VDD = 3V BRITE = 1.25V, RAMP_C = 2V, VDD = 3V 0 10 15 0 1.12 0.8 70 -15 20 0 -10 -10 2.5 400 50 70 1.25 1.5 200 -40 60 3 250 3 1100 110 120 VDD 1.38 10 700 -80 100 VDD 10 500 10 V µmho µA µA V V mA µmho µA µA V mV ns mV ns OUTPUT BUFFER BLOCK Output Sink Current ISK_OUTBUF Output Source Current ISOUT_BUF AOUT, BOUT = VDD = 3V AOUT, BOUT = 1V, VDD = 3V AOUT, BOUT = 0V, VDD = 3V AOUT, BOUT = 2V, VDD = 3V 25 20 -35 -20 45 35 -50 -40 85 85 85 85 mA mA mA mA 1.02 V µA kΩ V V mV mV BIAS CONTROL BLOCK Copyright © 2000 Rev. 1.2a, 2005-01-27 VIR IMAX_IR RO_VBG VEN3V VEN5.5 VH_EN3 VH_EN5.5 .975 Design Reference Only Design Reference Only VDD = 3V VDD = 5.5V 1.5 2.7 50 10 1.9 3.2 450 350 2.4 3.6 ELECTRICALS O Voltage at Pin I_R Pin I_R Maximum Source Current VBG Output Resistance ENABLE Logic Threshold – 3V ENABLE Logic Threshold – 5.5V ENABLE Threshold Hysteresis – 3V ENABLE Threshold Hysteresis – 5.5V Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 5 Not Recommended For New Design LX1686 I N T E G R A T E D Digital Dimming CCFL Controller IC P R O D U C T S P RODUCTION D ATA SHEET WWW . Microsemi .C OM BLOCK DIAGRAM CICOMP CVCOMP BRT ISNS VSNS Dimming Control Output Drivers ICOMP VCOMP PD_CR PWM Controllers RPD Voltage Error Amp - Phase Detector bs ol et e CPDN CPD + VCO VAMP 1.25V FVERT IAMP - Current Error Amp 0.5 - 2.5V CAFD VCO_C + CVCO AOUT VCOMP ICOMP + Q Current Comparator CLK OUT 2.5V - VDD_P A Q + + AFD_C Voltage Comparator 0V BOUT B RAMP_DOUT Auto Freq. Detect - Output Steering Logic VSS_P Bias Generator, UVLO, and VREF VDD ENA → PWR_GD Burst Comparator 2.50V ENABLE VDD_SW I_R BRITE Ri 50k VSS 50k ENA - 1.5V Triangle Wave Gen. VDD VDD + 300mV 255mV Ignite Open Lamp Comparator 0-3V O BRT_POS DIG_DIM RAMP_C CRAMP RAMP_R RRAMP2 BLOCK DIAGRAM PWM Ramp Generator TRI_C OLSNS RRAMP1 CTRI VDD Copyright © 2000 Rev. 1.2a, 2005-01-27 Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 6 Not Recommended For New Design LX1686 I N T E G R A T E D Digital Dimming CCFL Controller IC P R O D U C T S P RODUCTION D ATA SHEET PW 24-Pin Thin Small Shrink Outline (TSSOP) Dim A B C D E F G H L M P *LC MILLIMETERS MIN MAX 0.85 0.95 0.19 0.30 0.09 0.20 7.70 7.90 4.30 4.50 0.65 BSC 0.05 0.15 – 1.10 0.50 0.75 0° 8° 6.25 6.50 – 0.10 INCHES MIN MAX 0.033 0.037 0.007 0.012 0.0035 0.008 0.303 0.311 0.169 0.177 0.025 BSC 0.002 0.005 – .0433 0.020 0.030 0° 8° 0.246 0.256 – 0.004 bs ol et e 3 21 E WWW . Microsemi .C OM PACKAGE DIMENSIONS P F D A H SEATING PLANE B G L C M Note: Copyright © 2000 Rev. 1.2a, 2005-01-27 MECHANICALS O 1. Dimensions do not include mold flash or protrusions; these shall not exceed 0.155mm(.006”) on any side. Lead dimension shall not include solder coverage. Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 7 Not Recommended For New Design LX1686 I N T E G R A T E D P R O D U C T S Digital Dimming CCFL Controller IC P RODUCTION D ATA SHEET O bs ol et e WWW . Microsemi .C OM NOTES 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 © 2000 Rev. 1.2a, 2005-01-27 Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 8