ml4876 Microsemi Corporation, ml4876 Datasheet
ml4876
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ml4876 Summary of contents
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... LCD Backlight Lamp Driver with Contrast GENERAL DESCRIPTION The ML4876 is an ideal solution for driving small cold cathode fluorescent tubes (CCFL) used in liquid crystal display (LCD) backlight applications. It provides the dimming ballast control and the contrast control for the LCD display. ...
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... LEA– Negative input for lamp error amplifier 8 LEAOUT Output of lamp error amplifier 9 C Oscillator timing capacitor RTD Input to resonant threshold detector 2 ML4876 20-Pin SSOP (R20) FEA OUT 1 20 FEA– FEA VREF 5 ...
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... Voltage on Any Other Pin ............... –0.3V to VDD +0.3V Junction Temperature .............................................. 150°C Storage Temperature Range ..................... –65°C to 150°C Lead Temperature (Soldering 10 sec.) ..................... 260°C Thermal Resistance (q OPERATING CONDITIONS Temperature Range ML4876C ................................................... 0°C to 70°C ML4876E ............................................... –20°C to 70°C = 47pF Operating Temperature Range (Note CONDITIONS ...
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... ML4876 ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER FLYBACK REGULATOR (Continued) Current Limit Comparator Threshold Input Bias Current Propagation Delay Output Drivers Output High - F Gate Output Low - F Gate Rise & Fall Time HIGH VOLTAGE INVERTER Oscillator Nominal Frequency Discharge Current Peak Voltage Valley Voltage ...
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... Note 1: Limits are guaranteed by 100% testing, sampling, or correlation with worst case test conditions. Note 2: Actual load is 1200pF. The 2:1 transformer reflects an effective 2400pF. (Continued) CONDITIONS On/Off = 3V On/Off = 3V On/Off = “0”, HVDD = 12V T = 25° 25µA VREF ML4876 MIN TYP MAX UNITS 0.45 0.6 mA 200 350 µA 10 µA 2.47 2.5 2.53 V ...
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... ML4876 0. 47pF 200k LON ON/OFF Figure 1. ML4876 Typical Application Schematic L1 D2 C12 R16 200k 1.6M BRIGHTNESS ADJUST NOTE 1 R1, D3, Q2 ARE OPTIONAL AND ALLOWS A BATTERY VOLTAGE RANGE FROM 7V TO 28V. REMOVING THESE COMPONENTS AND CONNECTING DIRECTLY TO THE INPUT VOLTAGE ALLOWS 5 ...
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... FUNCTIONAL DESCRIPTION The ML4876 consists of a PWM regulator, a lamp driver/ inverter, a linear regulator, a flyback regulator, and control circuits. This IC, in conjunction with external components, converts a DC battery voltage into the high voltage and high frequency ac signal required to start and drive miniature cold cathode fluorescent lamps. In addition it generates the DC voltage for the contrast requirements of LCD screens ...
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... LOGIC CONTROL The ML4876 is controlled by a two logic inputs and ON/OFF. A logic level high on the L ON pin enables just the lamp driver. A logic zero on the L ON pin disable the lamp driver only ...
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... ORDERING INFORMATION PART NUMBER ML4876CR (END OF LIFE) ML4876ER (OBSOLETE) © Micro Linear 1998 registered trademark of Micro Linear Corporation. All other trademarks are the property of their respective owners. Products described herein may be covered by one or more of the following U.S. patents: 4,897,611; 4,964,026; 5,027,116; 5,281,862; 5,283,483; 5,418,502; ...