LT1182/LT1183/LT1184/LT1184F - CCFL/LCD …

1 1LT1182/LT1183/LT1184/LT1184 FCCFL/LCD ContrastSwitching RegulatorsnWide Input Voltage Range: 3V to 30 VnLow Quiescent CurrentnHigh Switching Frequency: 200kHznCCFL Switch : , LCD Switch: 625mAnGrounded or Floating Lamp ConfigurationsnOpen-Lamp ProtectionnPositive or Negative Contrast CapabilityFEATURESDESCRIPTIONUAPPLICATIO NSUThe LT 1182/LT1183 are dual current mode switchingregulators that provide the control function for Cold Cath-ode Fluorescent Lighting ( ccfl ) and Liquid Crystal Display(LCD) Contrast. The LT1184/LT1184F provide only theCCFL function. The ICs include high current, high efficiencyswitches, an oscillator, a reference, output drive logic,control blocks and protection circuitry. The LT1182 per-mits positive or negative voltage LCD contrast LT1183 permits unipolar contrast operation and pinsout an internal reference. The LT1182/LT1183 supportgrounded and floating lamp configurations. The LT1184 Fsupports grounded and floating lamp configurations.

2 TheLT1184 supports only grounded lamp configurations. ThenNotebook and Palmtop ComputersnPortable InstrumentsnAutomotive DisplaysnRetail Terminals90% Efficient Floating ccfl Configuration with Dual Polarity LCD ContrastTYPICAL APPLICATIONU, LTC and LT are registered trademarks of Linear Technology Corporation. C12 F 35 VBAT 8V TO 28 VPOSCONNEGCON1182/3 TA01 EITHER NEGCON OR POSCON MUST BE GROUNDED. GROUNDING NEGCON GIVES VARIABLE POSITIVE CONTRAST FROM 10V TO 30V. GROUNDING POSCON GIVES VARIABLE NEGATIVE CONTRAST FROM 10V TO 2 3 4 5 6 7 816 15 14 13 12 11 10 9 ICCFL DIO ccfl VC AGND SHDN LCD VCCCFL VSW BULB BAT ROYER VIN FBP FBN LCD VSWCCFL PGNDLCD PGNDLT1182 LAMPUP TO 6mA106L1L3R1 750 L2 100 H3 2154+++ALUMINUM ELECTROLYTIC IS RECOMMENDED FOR C3B WITH AN ESR TO PREVENT DAMAGE TO THE LT1182 HIGH-SIDE SENSE RESISTOR DUE TO SURGE CURRENTS AT TURN-ON. C7, 1 FC1* FD1 1N5818D2 1N914D4 1N914V (PWM) 0V TO 5V 1kHz PWMSHUTDOWNC8, FR7, 10KC5 1000pFR2 220kR3 100kC3A F 35VC11 22 F 35VR13 1%R14 1%5VR10, 10k, 1%R9, , 1%C4 FVIN 3VD3 1N5934A 24VC3B F 35VC2 27pF 3kV+C1 MUST BE A LOW LOSS CAPACITOR, C1 = WIMA MKP-20 Q1, Q2 = ZETEX ZTX849 OR ROHM 2SC5001 L1 = COILTRONICS CTX210605 L2 = COILTRONICS CTX100-4 L3 = COILTRONICS CTX02-12403 *DO NOT SUBSTITUTE COMPONENTS COILTRONICS (407) 241-7876 Q2*Q1*N = 1:2 0 A TO 45 A ICCFL CURRENT GIVES 0mA TO 6mA BULB CURRENT.

3 THIS IS EQUAL TO 0% TO 90% DUTY CYCLE FOR THE PWM 20kR5, , 1%C6 FR4 1%+D5 BAT85C10 FR11, 20k, 1%C9, F2 4 69 + ccfl BACKLIGHT APPLICATION CIRCUITS CONTAINED IN THIS DATA SHEET ARE COVERED BY PATENT NUMBER 5408162 AND OTHER PATENTS PENDING 2LT1182/LT1183/LT1184/LT1184 FDESCRIPTIONU current. An active low shutdown pin typically reduces totalsupply current to 35 A for standby operation. A 200kHzswitching frequency minimizes the size of required mag-netic components. The use of current mode switchingtechniques with cycle-by-cycle limiting gives high reliabil-ity and simple loop frequency compensation. The LT1182/LT1183/LT1184/LT1184F are all available in 16-pin nar-row SO pin out the reference for simplified pro-gramming of lamp LT1182/LT1183/LT1184/LT1184F operate with inputsupply voltages from 3V to 30V. The ICs also have abattery supply voltage pin that operates from to LT1182/LT1183 draw 9mA typical quiescent currentwhile the LT1184/LT1184F draw 6mA typical quiescentVIN, BAT, Royer, Bulb.

4 30 VCCFL VSW, LCD 60 VShutdown .. 6 VICCFL Input Current .. 10mADIO Input Current (Peak, < 100ms) .. 100mALT1182: FBP, FBN, LT1183: FB Pin Current .. 2mAABSOLUTE MAXIMUM RATINGSWWWUPACKAGE/ORDER INFORMATIONWUUTJMAX = 100 C, JA = 100 C/WTJMAX = 100 C, JA = 100 C/WConsult factory for Industrial and Military grade partsLT1183 CSORDER PARTNUMBERTJMAX = 100 C, JA = 100 C/WTJMAX = 100 C, JA = 100 C/WLT1182 CSORDER PARTNUMBERLT1184 CSORDER PARTNUMBERLT1184 FCSLT1183/LT1184/1184F: REF Pin Source Current .. 1mAJunction Temperature (Note 1) .. 100 COperating Ambient Temperature Range .. 0 C to 100 CStorage Temperature Range .. 65 C to 150 CLead Temperature (Soldering, 10 sec) .. 300 CORDER PARTNUMBERTOP VIEWS PACKAGE 16-LEAD PLASTIC SOCCFL PGND ICCFL DIO ccfl VC AGND SHUTDOWN LCD VC LCD PGNDCCFL VSW BULB BAT ROYER VIN FBP FBN LCD VSW1 2 3 4 5 6 7 816 15 14 13 12 11 10 9 TOP VIEWS PACKAGE 16-LEAD PLASTIC SOCCFL PGND ICCFL DIO ccfl VC AGND SHUTDOWN NC NCCCFL VSW BULB BAT NC VIN REF NC NC1 2 3 4 5 6 7 816 15 14 13 12 11 10 9 TOP VIEWS PACKAGE 16-LEAD PLASTIC SOCCFL PGND ICCFL DIO ccfl VC AGND SHUTDOWN LCD VC LCD PGNDCCFL VSW BULB BAT ROYER VIN REF FB LCD VSW1 2 3 4 5 6 7 816 15 14 13 12 11 10 9 TOP VIEWS PACKAGE 16-LEAD PLASTIC SOCCFL PGND ICCFL DIO ccfl VC AGND SHUTDOWN NC NCCCFL VSW BULB BAT ROYER VIN REF NC NC1 2 3 4 5 6 7 816 15 14 13 12 11 10 93LT1182/LT1183/LT1184/LT1184 FSYMBOLPARAMETERCONDITIONSMINTYPMAXUNITS IQS upply CurrentLT1182/LT1183: 3V VIN 30Vl914 mALT1184/LT1184F.

5 3V VIN Supply CurrentSHUTDOWN = 0V, ccfl VC = LCD VC = Open (Note 2)3570 ASHUTDOWN Input Bias CurrentSHUTDOWN = 0V, ccfl VC = LCD VC = Open3 6 ASHUTDOWN Threshold FrequencyMeasured at ccfl VSW and LCD VSW, ISW = 50mA,175200225kHzICCFL = 100 A, ccfl VC = Open, (LT1182) FBN = FBP =1V, (LT1183) FB = 1V, (LT1182/LT1183) LCD VC = Openl160200240kHzDC(MAX)Maximum Switch Duty CycleMeasured at ccfl VSW and LCD VSW8085%l7585%BVSwitch Breakdown VoltageMeasured at ccfl VSW and LCD VSW6070 VSwitch Leakage CurrentVSW = 12V, Measured at ccfl VSW and LCD VSW20 AVSW = 30V, Measured at ccfl VSW and LCD VSW40 AICCFL Summing Voltage3V VIN 30V, Measured on LT1182 VIN 30V, Measured on LT1184 ICCFL Summing Voltage forICCFL = 0 A to 100 A515mV Input Programming CurrentCCFL VC Offset Sink CurrentCCFL VC = , Positive Current Measured into Pin 5515 A ccfl VC Source Current forICCFL = 25 A, 50 A, 75 A, 100 A, A/ A ICCFL Programming CurrentCCFL VC = VC to DIO Current Servo RatioDIO = 5mA out of Pin, Measure IVC at ccfl VC = A/mACCFL VC Low Clamp VoltageVBAT VBULB = Bulb Protect Servo VC High Clamp VoltageICCFL = 100 VC Switching ThresholdCCFL VSW DC = 0% High-Side Sense Servo CurrentICCFL = 100 A, IVC = 0 A at ccfl VC = High-Side Sense Servo CurrentBAT = 5V to 30V, ICCFL = 100 A.

6 VLine RegulationIVC = 0 A at ccfl VC = High-Side Sense Supply CurrentCurrent Measured into BAT and Royer Pinsl50100150 ABulb Protect Servo VoltageICCFL = 100 A, IVC = 0 A at ccfl VC = , Voltage Measured Between BAT and Bulb PinsBulb Input Bias CurrentICCFL = 100 A, IVC = 0 A at ccfl VC = AILIM1 ccfl Switch Current LimitDuty Cycle = 50% Cycle = 75% (Note 3) Switch On-ResistanceCCFL ISW = IQSupply Current Increase DuringCCFL ISW = 1A2030mA/A ISW1 ccfl Switch On-TimeVREFR eference VoltageMeasured at REF (Pin 11) on LT1183/LT1184 Output ImpedanceMeasured at REF (Pin 11) on LT1183l204570 Measured at REF (Pin 11) on LT1184/LT1184Fl51530 ELECTRICAL CHARACTERISTICSTA = 25 C, VIN = 5V, BAT = Royer = Bulb = 12V, ICCFL = SHUTDOWN = ccfl VSW = Open, DIO = GND, ccfl VC = ,(LT1182/LT1183) LCD VC = , LCD VSW = Open, (LT1182) FBN = FBP = GND, (LT1183) FB = GND,(LT1183/LT1184/LT1184F) REF = Open, unless otherwise CHARACTERISTICSSYMBOLPARAMETERCONDITIONS MINTYPMAXUNITSVREF ICCFL Summing VoltageMeasured on ICCFL Summing VoltageMeasured on LT1184 FBP/FB Reference VoltageLT1182: Measured at FBP Pin, FBN = 1V, LCD VC = : Measured at FB Pin, LCD VC = Voltage Line Regulation3V VIN 30V, LCD VC = / VFBP/FB Input Bias CurrentLT1182: FBP = REF1, FBN = 1V, LCD VC = : FB = REF1, LCD VC = ALCD FBN/FB Offset VoltageLT1182: Measured at FBN Pin, FBP = 0V, LCD VC = 20 12 4mVLT1183: Measured at FB Pin, LCD VC = 27 12 1mVOffset Voltage Line Regulation3V VIN 30V, LCD VC = / VFBN/FB Input Bias CurrentLT1182: FBN = Offset Voltage, FBP = 0V, LCD VC = : FB = Offset Voltage, LCD VC = AgmFBP/FB to LCD VC TransconductanceLT1182: IVC = 25 A, FBN = 1V6509001150 mhosLT1183: IVC = 25 Al5009001300 mhosFBN/FB to LCD VC TransconductanceLT1182: IVC = 25 A, FBP = GND5508001050 mhosLT1183.

7 IVC = 25 Al4008001200 mhosLCD Error Amplifier Source CurrentLT1182: FBP = FBN = 1V or ,l50100175 ALT1183: FB = 1V or Error Amplifier Sink CurrentLT1182: FBP = FBN = or ,l35100175 ALT1183: FB = or VC Low Clamp VoltageLT1182: FBP = FBN = , LT1183: FB = VC High Clamp VoltageLT1182: FBP = FBN = 1V, LT1183: FB = VC Switching ThresholdLT1182: FBP = FBN = 1V, LT1183: FB = 1V, VSW DC = 0% Switch Current LimitDuty Cycle = 50% Cycle = 75% (Note 3) Switch On-ResistanceLCD ISW = IQSupply Current Increase DuringLCD ISW = ISW2 LCD Switch On-TimeSwitch Minimum On-TimeMeasured at ccfl VSW and LCD sTA = 25 C, VIN = 5V, BAT = Royer = Bulb = 12V, ICCFL = SHUTDOWN = ccfl VSW = Open, DIO = GND, ccfl VC = ,(LT1182/LT1183) LCD VC = , LCD VSW = Open, (LT1182) FBN = FBP = GND, (LT1183) FB = GND,(LT1183/LT1184/LT1184F) REF = Open, unless otherwise l denotes specifications which apply over the specified operatingtemperature 1: TJ is calculated from the ambient temperature TA and powerdissipation PD according to the following formula:LT1182CS/LT1183CS/LT1184CS/LT118 4 FCS: TJ = TA + (PD 100 C/ W)Note 2: Does not include switch 3.

8 For duty cycles (DC) between 50% and 75%, minimumguaranteed switch current is given by ILIM = ( DC) for the ccfl regulator and ILIM = ( DC ) for the LCD contrast regulator due tointernal slope compensation ( C) 75 LCD DUTY CYCLE (%)8791959389858177125 150LT1182 G09837975 25 0 5025 5075 100175 TEMPERATURE ( C) 75 ccfl DUTY CYCLE (%)8791959389858177125 150LT1182 G07837975 25 0 5025 5075 100175 TYPICAL PERFORMANCE CHARACTERISTICS UWLT1184/LT1184F Supply Currentvs TemperatureLT1182/LT1183 Supply Currentvs TemperatureShutdown Input Bias Currentvs TemperatureTEMPERATURE ( C)0 SHUTDOWN INPUT BIAS CURRENT ( A)246531 252575125LT1182 G04175 50 75050100150 VIN = 5 VVIN = 3 VVIN = 30 VShutdown Threshold Voltagevs TemperatureTEMPERATURE ( C) THRESHOLD VOLTAGE (V) 252575125LT1182 G05175 50 75050100150 TEMPERATURE ( C) 75 ccfl FREQUENCY (kHz)220240125LT1182 G06200180160 25 2575175210230190170100 50050150 VIN = 30V VIN = 3 VCCFL Frequency vs TemperatureLCD Duty Cycle vs TemperatureLCD Frequency vs TemperatureCCFL Duty Cycle vs TemperatureShutdown Currentvs TemperatureTEMPERATURE ( C) 75 SUPPLY CURRENT (mA)1012141311975125LT1182 G01864 25 500501001502575175 VIN = 30V VIN = 3 VTEMPERATURE ( C) 75 SHUTDOWN CURRENT ( A)608O1009070503010125LT1182 G0340200 25 500501001502575175 VIN = 30 VVIN = 5 VVIN = 3 VTEMPERATURE ( C) 75 SUPPLY CURRENT (mA)681097531125LT1182 G02420 25 500501001502575175 VIN = 30 VVIN = 3 VTEMPERATURE ( C) 75 LCD FREQUENCY (kHz)220240125LT1182 G08200180160 25 2575175210230190170100 50050150 VIN = 3 VVIN = 30V6LT1182/LT1183/LT1184/LT1184 FTYPICAL PERFORMANCE CHARACTERISTICS UWICCFL Summing Voltagevs TemperatureTEMPERATURE ( C)ICCFL SUMMING VOLTAGE (V)

9 252575125LT1182 G10175 50 75050100150 VIN = 5 VVIN = 3 VVIN = 30V ccfl VC Source Current for ICCFL Programming Currentvs TemperatureCCFL VC to DIO Current ServoRatio vs TemperatureICCFL PROGRAMMING CURRENT ( A) 543210 1 2 3 4 5 6 7 8 9 104080120160LT1182 G1120020060100140180T = 55 CT = 25 CT = 125 C ICCFL SUMMING VOLTAGE (mV)TEMPERATURE ( C) 3 ccfl VC SINK OFFSET CURRENT ( A) 110 21096875324 75125 150 25 0 5025 5075 100175 ccfl VC = VC = VC = G12 TEMPERATURE ( C)0 POSITIVE DIO VOLTAGE (V) 252575125LT1182 G14175 50 75050100150I(DIO) = 1mAI(DIO) = 5mAI(DIO) = 10mAPositive DIO Voltagevs TemperatureNegative DIO Voltagevs TemperatureCCFL VC High Clamp Voltagevs TemperatureCCFL VC Low Clamp Voltagevs TemperatureTEMPERATURE ( C)0 ccfl VC LOW CLAMP VOLTAGE (V) 252575125LT1182 G17175 50 75050100150 ICCFL Summing VoltageLoad RegulationCCFL VC Offset Sink Currentvs TemperatureTEMPERATURE ( C) VC HIGH CLAMP VOLTAGE (V) 5050100LT1182 25075125 TEMPERATURE ( C) ccfl VC SOURCE CURRENT FOR ICCFL PROGRAMMING CURRENT ( A/ A) 252575125LT1182 G13175 50 75050100150 ICCFL = 10 AICCFL = 50 AICCFL = 100 ATEMPERATURE ( C) 75 ccfl VC DIO CURRENT SERVO RATIO ( A/mA)101103125LT1182 G16999795 25 25751751001029896100 50050150I(DIO) = 1mAI(DIO) = 5mAI(DIO) = 10mATEMPERATURE ( C) 75 NEGATIVE DIO VOLTAGE (V) 25 50050150I(DIO) = 1mAI(DIO) = 5mAI(DIO) = 10mA7LT1182/LT1183/LT1184/LT1184 FTYPICAL PERFORMANCE CHARACTERISTICS UWCCFL VC Switching ThresholdVoltage vs TemperatureTEMPERATURE ( C) VC SWITCHING THRESHOLD VOLTAGE (V) 5050100LT1182 25075125 LCD VC Low Clamp Voltagevs TemperatureTEMPERATURE ( C) 50 750 LCD VC LOW CLAMP VOLTAGE (V) 2525100125 LCD VC High Clamp Voltagevs TemperatureTEMPERATURE ( C) VC HIGH CLAMP VOLTAGE (V) 5050100LT1182 25075125 LCD VC Switching ThresholdVoltage vs TemperatureTEMPERATURE ( C) VC SWITCHING THRESHOLD VOLTAGE (V)

10 5050100LT1182 25075125 ccfl High-Side Sense NullCurrent vs TemperatureTEMPERATURE ( C) HIGH-SIDE SENSE NULL CURRENT (A) 252575125LT1182 G23175 50 75050100150 ccfl High-Side Sense Null CurrentLine Regulation vs TemperatureTEMPERATURE ( C) 75 ccfl HIGH-SIDE SENSE LINE REGULATI0N (%V) 25 50050150 TEMPERATURE ( C) 75 ccfl HIGH-SIDE SENSE SUPPLY CURRENT ( A)1101301501401201008060125 150LT1182 G25907050 250 5025 5075 100175 ccfl High-Side Sense SupplyCurrent vs TemperatureBulb Protect Servo Voltagevs TemperatureTEMPERATURE ( C) 75 BULB PROTECT SERVO VOLTAGE (V) 150LT1182 25 0 5025 5075 100175 ICCFL = 10 AICCFL = 50 AICCFL = 100 ABulb Input Bias Currentvs TemperatureTEMPERATURE ( C)BULB INPUT BIAS CURRENT ( A)6810LT1182 G27420 75125 150 25 0 5025 5075 1001758LT1182/LT1183/LT1184/LT1184 FTYPICAL PERFORMANCE CHARACTERISTICS UWFBP Input Bias Currentvs TemperatureFBP to LCD VC Transconductancevs TemperatureLCD FBP Referencevs TemperatureTEMPERATURE ( C) FBP REFERENCE VOLTAGE (V) 252575125LT1182 G28175 50 75050100150 TEMPERATURE ( C) 75 FBP INPUT BIAS CURRENT ( A) 150LT1182 25 0 5025 5075 100175 LCD FBN Offset Voltagevs TemperatureTEMPERATURE ( C) 27 LCD FBN OFFSET VOLTAGE (mV) 23 19 21 25 1 3 9 5 7 11 15 17 13 75125 150 25 0 5025 5075 100175 FBN to LCD VC Transconductancevs TemperatureLT1184/84F REF OutputImpedance vs TemperatureTEMPERATURE ( C) 75 FBN TO LCD VC TRANSCONDUCTANCE ( mhos)10001200125LT1182 G34800600400 25 25751759001100700500100 50050150 TEMPERATURE ( C) 75 FBP TO LCD VC TRANSCONDUCTANCE ( mhos)11001300125LT1182 G33900700500 25 257517510001200800600100 50050150 TEMPERATURE ( C)0 FBP REFERENCE VOLTAGE LINE REGULATION (%/V)