lt1186f Linear Technology Corporation, lt1186f Datasheet
lt1186f
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lt1186f Summary of contents
Page 1
... ALUMINUM ELECTROLYTIC IS RECOMMENDED FOR C3A AND C3B. MAKE 3CB ESR 0.5 TO PREVENT DAMAGE TO THE LT1186F HIGH-SIDE SENSE RESISTOR DUE TO SURGE CURRENTS AT TURN-ON C1 MUST BE A LOW LOSS CAPACITOR WIMA MKP-20 Q1 ZETEX ZTX849 OR ROHM 2SC5001 CCFL Switching Regulator face modes including standard SPI mode and pulse mode. ...
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... Digital Inputs ................................ – 0. Digital Outputs .............................. – 0. DAC Output Voltage ....................... – 20V to V Junction Temperature (Note 1) ........................... 100 C Operating Ambient Temperature Range LT1186FC ............................................ 100 C LT1186FI .......................................... – 100 C Storage Temperature Range ................ – 150 C Lead Temperature (Soldering, 10 sec)................ 300 C ELECTRICAL CHARACTERISTICS SHUTDOWN = ...
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... 3. 3.3V 400 5V 400 3.3V 1mA 5V 2mA See Test Circuits See Test Circuits See Test Circuits LT1186F = Open Three-State, DIO = I SW OUT OUT MIN TYP MAX UNIT 0.93 1.00 1.07 0.91 1.00 1.07 0.1 0.16 50 100 150 6.5 7.0 7 1.25 1.9 3.0 0.9 1.6 2.6 0.6 1.0 20 ...
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... CLK Note 3: For duty cycles (DC) between 50% and 80%, minimum guaranteed switch current is given by I LT1186F due to internal slope compensation circuitry. and power A Note 4: Timings for all input signals are measured at 0.8V for a High-to- Low transition and 2.0V for a Low-to-High transition. Note 5: Timings are guaranteed but not tested. ...
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... TEMPERATURE ( C) LT1186F • G11 V High Clamp Voltage C vs Temperature 2.4 2.3 2.2 2.1 2.0 1.9 1.8 1.7 125 150 175 –75 – 50 – TEMPERATURE ( C) LT1186F • G14 = 1.5V 125 150 175 LT1186F • G09 100 125 150 175 LT1186F • G12 150 175 100 125 LT1186F • G15 5 ...
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... 1 125 C MINIMUM 1.0 0 DUTY CYCLE (%) LT1186F • G23 BULB Input Bias Current vs Temperature –75 – 50 – 100 125 150 175 TEMPERATURE ( C) LT1186F • G18 High-Side Sense Null Current Line Regulation vs Temperature ...
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... LT1186F DAC Bias Voltage OUT OUT 3. –20 –15 –10 – OUTPUT BIAS VOLTAGE (V) LT1186F • G27 pin provides both stable ...
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... I The programming current is sourced from the I sunk by the I V (Pin 12): This is the supply pin for the LT1186F. The CC IC accepts an input voltage range of 3V minimum to 6.5V maximum with little change in quiescent current (zero switch current). An internal, low-dropout regulator pro- vides a 2 ...
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... CONDITIONS SUCH THAT THE OUTPUT IS LOW UNLESS WAVEFORM 1 DISABLED LT1186F • TC02 LT1186F pin down. This action transfers the entire C (Pin 16): This pin is the collector of the internal Voltage Waveforms for 2.0V CS 0.8V D OUT 2. OUT 0.4V 90% 10% LT1186F • TC04 9 ...
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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 REGULATOR SHUTDOWN LOCKOUT 200kHz OSC 0.1 – Q11 ...
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... Referring to the block diagram for the LT1186F, the switch turns ON at the start of each oscillator cycle. The switch turns OFF when switch current reaches a predetermined level. The control of output lamp current is obtained by using the output of a unique programming block to set current trip level ...
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... CLK decreases the counter by one-step. The last two LSBs CS are always zero in this mode. I (50 A)/255. The upper 6-bit counter = B LT1186F • F01b configure the LT1186F into increment-only 1 0 mode, tie CS and ALWAYS HIGH D ...
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... The last two LSBs are always zero in this mode OUT (50 A)/255. The upper 6-bit counter = configure the LT1186F into increment decrement mode, tie and pulse the UP/DN pin CC once on power-up. Simplified Lamp Current Programming ...
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... Figure 3 Grounded Lamp Configuration In a grounded lamp configuration, the low voltage side of the lamp connects directly to the LT1186F DIO pin. This pin is the common connection between the cathode and anode of two internal diodes. In previous grounded lamp solutions, these diodes were discrete units and are now integrated onto the IC, saving cost and board space ...
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... Royer trans- former. Previous solutions have used an external preci- sion shunt and high-side sense amplifier configuration. This approach has been integrated onto the LT1186F for simplicity of design and ease of use. An internal 0.1 resistor monitors the Royer converter current and con- nects between the input terminals of a high-side sense amplifier – ...
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... LT1186F U U APPLICATIONS INFORMATION References 1. Williams, Jim. August 1992. Illumination Circuitry for Liquid Crystal Displays . Linear Technology Corporation, 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 ...