LM3434SQX National Semiconductor Corporation, LM3434SQX Datasheet
LM3434SQX
Related parts for LM3434SQX
LM3434SQX Summary of contents
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... Additional features include thermal shutdown, V under-voltage lockout, and logic level shut- CC down mode. The LM3434 is available in a low profile LLP-24 package. Typical Application Circuit © 2010 National Semiconductor Corporation LM3434 Features ■ Operating input voltage range of -9V to -30V w.r.t. LED anode ■ ...
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... Connection Diagram Ordering Information Order Number Spec. LM3434SQ NOPB LM3434SQX NOPB Pin Descriptions Pin Name ADJ DIM CGND COMP www.national.com Top View 24-Lead LLP NS Package Number SQA24A Package ...
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Pin Name Low side FET gate drive power bypass connection and boost diode anode connection. Tie 2.2µF capacitor between V 16 BST High side "synchronous" FET drive bootstrap rail High side "synchronous" FET gate ...
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Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications EN, DIM, ADJ to CGND IN COMP BST ...
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Symbol Parameter FUNCTIONAL CONTROL V V undervoltage lockout INUVLO undervoltage lockout CCUVLO CC EE thresholds V Enable threshold, with respect EN to CGND R Enable pin pullup resistor EN V DIM logic input threshold DIM ...
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Typical Performance Characteristics Efficiency vs. LED Forward Voltage (V -V CGND EE Efficiency vs. LED Forward Voltage ( 14V) CGND EE V vs. V SENSE (V = 5.0V) IN www.national.com = 9V) 30098923 30098921 ADJ 30098919 6 Efficiency ...
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V vs. Temperature SENSE (ADJ = 1.0V) Startup Waveform nominal 3.3V -12V 3V open LED IN EE LED Top trace: EN input, 2V/div, DC Middle trace: V input current, ...
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Operation CURRENT REGULATOR OPERATION The LM3434 is a controller for a Continuous Conduction Buck Converter. Because of its buck topology and operation in the continuous mode, the output current is very well controlled. It only varies within a switching frequency ...
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RECOMMENDED OPERATING FREQUENCY AND ON TIME "TIME " CALCULATION ON Although the switching frequency can be set over a wide range, the following equation describes the recommended frequency selection given inexpensive magnetic materials available today: In the above equation A=1.2 ...
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LAYOUT CONSIDERATIONS The LM3434 is a high performance current driver so attention to layout details is critical to obtain maximum performance. The most important PCB board design consideration is mini- mizing the loop comprised by the main FET, synchronous FET, ...
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Application Information FIGURE 10A Output Application Circuit FIGURE 20A Output Application Circuit 11 30098916 30098917 www.national.com ...
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Some Recommended Inductors (Others May Be Used) Manufacturer Coilcraft GA3252-AL series, SER1360 series, and SER2900 series Coiltronics Pulse Some Recommended Input/Bypass Capacitors (Others May Be Used) Manufacturer Vishay Sprague Taiyo Yuden Cornell Dubilier MuRata Some Recommended MOSFETs (Others May Be ...
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Physical Dimensions inches (millimeters) unless otherwise noted For Ordering, Refer to Ordering Information Table LLP-24 Pin Package (SQA) NS Package Number SQA24A 13 www.national.com ...
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