LT1186FCS Linear Technology, LT1186FCS Datasheet
LT1186FCS
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LT1186FCS Summary of contents
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... The LT1186F is available in a 16-pin nar- row SO package. , LTC and LT are registered trademarks of Linear Technology Corporation. Bits-to-Nits is a trademark of Linear Technology Corporation. 1 Nit = 1 Candela/meter CCFL BACKLIGHT APPLICATION CIRCUITS CONTAINED IN THIS DATA SHEET ARE COVERED BY U.S. PATENT NUMBER 5408162 ...
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... DIO = 5mA out of Pin, Measure I CCFL – BULB Protect Servo Voltage BAT BULB I = 100 A CCFL CCFL INFORMATION TOP VIEW ORDER PART 1 16 NUMBER CCFL BULB 3 14 BAT LT1186FCS 4 13 ROYER LT1186FIS OUT OUT PACKAGE 16-LEAD PLASTIC SO = 100 C, = 100 C Open Three-State, DIO = I SW OUT ...
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ELECTRICAL CHARACTERISTICS SHUTDOWN = 3.3V, BAT = Royer = BULB = 12V CLK = GND, CCFL V = 0.5V, unless otherwise specified. C SYMBOL PARAMETER ...
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... CS High Time CSHI 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 LT1186FCS )(100 C/ Note 2: Does not include switch leakage TYPICAL PERFORMANCE CHARACTERISTICS Supply Current vs Temperature ...
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W U TYPICAL PERFORMANCE CHARACTERISTICS I Summing Voltage CCFL vs Temperature 0.53 0.52 0.51 0.50 0.49 0.48 0.47 0.46 0.45 0.44 0.43 0.42 0.41 0.40 0.39 0.38 –75 – 50 – 100 125 150 TEMPERATURE ( ...
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LT1186F W U TYPICAL PERFORMANCE CHARACTERISTICS V Switching Threshold C vs Temperature 1.3 1.2 1.1 1.0 0.9 0.8 0.7 0.6 –75 – 100 125 150 175 – TEMPERATURE ( C) LT1186F • G16 High-Side Sense ...
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... The regulator provides a separate analog ground and power ground 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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LT1186F PIN FUNCTIONS AGND (Pin 5): This is the low current analog ground the negative sense terminal for the internal 1.24V refer- ence and the I summing voltage in the LT1186F. CCFL Connect low current ...
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PIN FUNCTIONS BAT (Pin 14): This pin connects to the battery or AC wall adapter voltage from which the CCFL Royer converter operates. This voltage is typically higher than the V supply voltage but can equal V ...
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LT1186F W BLOCK DIAGRAM LT1186F DAC Programmable CCFL Switching Regulator SHUTDOWN 6 SHUTDOWN + CCFL – V1 0.465V 2 I CCFL POWER-ON RESET CLK BAT UNDER- THERMAL 2.4V VOLTAGE ...
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U U APPLICATIONS INFORMATION Introduction Current generation portable computers and instruments use backlit Liquid Crystal Displays (LCDs). Cold Cathode Fluorescent Lamps (CCFLs) provide the highest available efficiency in back lighting the display. Providing the most light out for the least ...
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LT1186F U U APPLICATIONS INFORMATION circuitry provides a ratio of switch current to driver current of about 50:1. 8-Bit Current Output DAC The 8-bit current output DAC is guaranteed monotonic and is digitally adjustable by the 8-bit counter in 256 ...
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U U APPLICATIONS INFORMATION CS t CKS CLK t CSS Hi OUT 2-Wire Interface (Pulse Mode) In increment/decrement pulse mode, a logic high at UP/ DN programs the counter into increment ...
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LT1186F APPLICATIONS INFORMATION lation due to its shunt capacitance. Use a decoupling resistor of several kilohms between the I I pin if excessive trace stray capacitance exists. Nor- OUT mally, this resistor is not required. In some ...
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... This issue only exists with floating lamp circuits as 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. ...
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... Application Note 49. 2. Williams, Jim. August 1993. Techniques for 92% Effi- cient LCD Illumination . Linear Technology Corporation, Application Note 55. 3. Bonte, Anthony. March 1995. LT1182 Floating CCFL with Dual Polarity Contrast . Linear Technology Corpora- tion, Design Note 99. PACKAGE DESCRIPTION 0.010 – 0.020 45 0.053 – ...