LM3434SQX/NOPB National Semiconductor, LM3434SQX/NOPB Datasheet
LM3434SQX/NOPB
Specifications of LM3434SQX/NOPB
Related parts for LM3434SQX/NOPB
LM3434SQX/NOPB 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 ...
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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 CGND, DIMR, CSP, CSN (Note output DIMO to DIMR LO output Electrical Characteristics Specifications in standard type face are for T Range ( T = − ...
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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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