LT1184CS Linear Technology, LT1184CS Datasheet

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... The LT1183 permits unipolar contrast operation and pins out an internal reference. The LT1182/LT1183 support grounded and floating lamp configurations. The LT1184F supports grounded and floating lamp configurations. The LT1184 supports only grounded lamp configurations. The , LTC and LT are registered trademarks of Linear Technology Corporation 6mA LAMP C2 27pF ...

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... ORDER PART NUMBER CCFL PGND I CCFL DIO LT1182CS CCFL V C AGND SHUTDOWN LCD V C LCD PGND T JMAX ORDER PART NUMBER CCFL PGND I CCFL DIO LT1184CS CCFL V C AGND SHUTDOWN JMAX TOP VIEW ORDER PART CCFL V NUMBER BULB 15 2 BAT 3 14 LT1183CS ...

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ELECTRICAL CHARACTERISTICS 5V, BAT = Royer = Bulb = 12V (LT1182/LT1183) LCD V = 0.5V, LCD (LT1183/LT1184/LT1184F) REF = Open, unless otherwise specified. SYMBOL PARAMETER I Supply Current ...

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... The denotes specifications which apply over the specified operating temperature range. Note calculated from the ambient temperature T J dissipation P according to the following formula: D LT1182CS/LT1183CS/LT1184CS/LT1184FCS SHUTDOWN = CCFL V = Open, DIO = GND, CCFL V CCFL SW = Open, (LT1182) FBN = FBP = GND, (LT1183 GND, CONDITIONS Measured on LT1183 ...

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W U TYPICAL PERFORMANCE CHARACTERISTICS LT1182/LT1183 Supply Current vs Temperature 30V –75 – 50 – 100 125 ...

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LT1182/LT1183/LT1184/LT1184F W U TYPICAL PERFORMANCE CHARACTERISTICS I Summing Voltage CCFL vs Temperature 0.53 0.52 0.51 0.50 0.49 0. 30V 0. 0.46 0. 0.44 IN 0.43 0.42 0.41 0.40 0.39 0.38 ...

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W U TYPICAL PERFORMANCE CHARACTERISTICS CCFL V Switching Threshold C Voltage vs Temperature 1.3 1.2 1.1 1.0 0.9 0.8 0.7 0.6 150 175 –75 – 50 – 100 125 TEMPERATURE ( C) LT1182 • G19 LCD ...

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LT1182/LT1183/LT1184/LT1184F W U TYPICAL PERFORMANCE CHARACTERISTICS LCD FBP Reference vs Temperature 1.274 1.264 1.254 1.244 1.234 1.224 1.214 –75 – 50 – 100 125 150 175 TEMPERATURE ( C) LT1182 • G28 LCD FBN Offset Voltage ...

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W U TYPICAL PERFORMANCE CHARACTERISTICS CCFL V Sat Voltage SW vs Switch Current 1.0 0 125 –5 C 0.6 0.5 0.4 0.3 0.2 0 0.3 0.6 0.9 ...

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... The regulators provide a separate analog ground and power ground(s) to isolate high current ground paths from low current signal paths. Linear Technology recommends the use of star-ground layout techniques. I (Pin 2): This pin is the input to the CCFL lamp current CCFL programming circuit ...

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... NPN power switch. LCD contrast switch current flows through this pin and permits internal, switch-current sensing. The regulators provide a separate analog ground and power ground(s) to isolate high current ground paths from low current signal paths. Linear Technology recom- mends star-ground layout techniques. 11 ...

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LT1182/LT1183/LT1184/LT1184F PIN FUNCTIONS LCD V (Pin 9): This pin is the collector of the internal SW NPN power switch for the LCD contrast regulator. The power switch provides a minimum of 625mA. Maximum switch current is a ...

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W BLOCK DIAGRAM LT1182/LT1183 CCFL/LCD Contrast Regulator Top Level Block Diagram SHUTDOWN 6 SHUTDOWN LCD DRIVE 2 LOGIC 2 ANTI- SAT2 COMP2 + I R2 LIM AMP2 0.25 – GAIN = 4 100 ...

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LT1182/LT1183/LT1184/LT1184F W BLOCK DIAGRAM LT1184/LT1184F CCFL Regulator Top Level Block Diagram SHUTDOWN 6 SHUTDOWN + CCFL 100 A – V REF V1 1.24V 0.465V 11 2 REF I CCFL LT1184/LT1184F: REFERENCE IS BROUGHT OUT TO PIN 1. ...

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U U APPLICATIONS INFORMATION Manufacturers offer a wide array of monochrome and color displays. LCD display types include passive matrix and active matrix. These displays differ in operating volt- age polarity (positive and negative contrast voltage dis- plays), operating voltage ...

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LT1182/LT1183/LT1184/LT1184F APPLICATIONS INFORMATION change in quiescent current. An active low shutdown pin typically reduces total supply current shutting off the 2.4V regulator and locking out switching action for standby operation. The ICs incorporate ...

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U U APPLICATIONS INFORMATION cycles. Lamp current is controlled by monitoring one-half of the average lamp current. The diode conducting on negative half cycles has one-tenth of its current diverted to the CCFL pin and nulls against the source current ...

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... U ized calibrated voltage and current probes, wideband RMS voltmeters, a photometer, and a calorimeter (for the backlight enthusiast). Linear Technology’s Application Note 55 and Design Note 101 contain detailed information regarding equipment needs. Input Supply Voltage Operating Range The backlight/LCD contrast control circuits must operate ...

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... Every aspect of the design is interrelated and any design change requires complete re-evaluation for all other critical design param- eters. Linear Technology has engineered one of the most complete test and evaluation setups for backlight designs and understands the issues and tradeoffs in achieving a compact, effficient and economical customer solution ...

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LT1182/LT1183/LT1184/LT1184F U TYPICAL APPLICATIONS 90% Efficient Grounded CCFL Configuration with Negative Polarity LCD Contrast C1 MUST BE A LOW LOSS CAPACITOR WIMA MKP-20 Q1 ZETEX ZTX849 OR ROHM 2SC5001 L1 = COILTRONICS CTX210605 L2 = COILTRONICS ...

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U TYPICAL APPLICATIONS LT1184F Floating CCFL with Potentiometer Control of Lamp Current ALUMINUM ELECTROLYTIC IS RECOMMENDED FOR C3B WITH AN ESR 0.5 TO PREVENT DAMAGE TO THE LT1184F HIGH-SIDE SENSE RESISTOR DUE TO SURGE CURRENTS AT TURN-ON. C1 MUST BE ...

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LT1182/LT1183/LT1184/LT1184F U TYPICAL APPLICATIONS LT1182/LT1183 I PWM Programming CCFL V (PWM 40.5k 40.5k 1kHz PWM AND R2 ARE IDEAL VALUES. 2.2 F ...

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... LCD PGND Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. LT1182/LT1183/LT1184/LT1184F N LT1182 LCD Contrast Positive Boost Converter ...

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... TYP : 499-3977 BAT 8V TO 28V L3 CTX50-4 COILTRONICS CTX50-4 C11 35V 1N914 NEGCON | OUT C11 1N914 + 35V 1182 TA14 0.386 – 0.394* (9.804 – 10.008 LT/GP 0495 10K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1995 IN 0.150 – 0.157* (3.810 – 3.988) ...