LM3311SQ National Semiconductor Corporation, LM3311SQ Datasheet
LM3311SQ
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LM3311SQ Summary of contents
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... HIOP version. The gate pulse modulation switch can operate with a VGH voltage 30V. The LM3311 is available in a low profile 24-lead LLP package. Typical Application Circuit © 2007 National Semiconductor Corporation Features ■ Boost converter with a 2A, 0.18Ω switch ■ ...
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... Connection Diagram Ordering Information Order Number Spec. LM3311SQ LM3311SQX LM3311SQ NOPB LM3311SQX NOPB LM3311SQ-HIOP LM3311SQX-HIOP LM3311SQ-HIOP NOPB LM3311SQX-HIOP NOPB Pin Descriptions Pin Name 1 NC Not internally connected. 2 VGHM Output of GPM circuit. This output directly drives the supply for the gate driver circuits. ...
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Pin Name 8 NEG Negative input terminal of the Op-Amp. 9 POS Positive input terminal of the Op-Amp. 10 AGND Analog ground for the step-up regulator, LDO, and Op-Amp. Connect directly to DAP and PGND beneath the device. 11 ADJ ...
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www.national.com 4 20126358 ...
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20126359 20126360 5 www.national.com ...
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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 Voltage FB Voltage V Voltage (Note 2) C SHDN Voltage FREQ AV IN Amplifier Inputs/Output LV ...
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Symbol Parameter UVP Undervoltage Protection Threshold I FREQ Pin Current FREQ Electrical Characteristics Specifications in standard type face are for T Range ( T = −40°C to +125°C). Unless otherwise specified V J Operational Amplifier Symbol Parameter V Input Offset ...
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Gate Pulse Modulation Symbol Parameter R VGH to VGHM Resistance VGH-VGHM R VGHM to RE Resistance VGHM-RE R VGH Resistance VGHM(OFF Current Voltage Threshold CE(TH) Electrical Characteristics Specifications in standard type face are for T ...
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Typical Performance Characteristics SHDN Pin Current vs. SHDN Pin Voltage FREQ Pin Current vs. Input Voltage CE Pin Current vs. Input Voltage SS Pin Current vs. Input Voltage 20126361 FB Pin Current vs. Temperature 20126363 VDPM Pin Current vs. VDPM ...
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VFLK Pin Current vs. VFLK Pin Voltage 1.28MHz Switching Quiescent Current vs. Input Voltage 1.28MHz Switching Quiescent Current vs. Temperature www.national.com 660kHz Switching Quiescent Current vs. Input Voltage 20126366 660kHz Switching Quiescent Current vs. Temperature 20126367 660kHz Switching Frequency vs. ...
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Switching Frequency vs. Temperature Non-Switching Quiescent Current vs. Input Voltage GPM Disabled Non-Switching Quiescent Current vs. Temperature GPM Disabled Switch Current Limit vs. Input Voltage 20126369 Non-Switching Quiescent Current vs. Input Voltage GPM Enabled 20126371 Non-Switching Quiescent Current vs. ...
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Power NMOS R vs. Input Voltage DSON 1.28MHz Max. Duty Cycle vs. Input Voltage 1.28MHz Max. Duty Cycle vs. Temperature www.national.com 660kHz Max. Duty Cycle vs. Input Voltage 20126375 660kHz Max. Duty Cycle vs. Temperature 20126383 1.28MHz Application Efficiency 20126376 ...
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Application Efficiency VGH Pin Bias Current vs. VGH Pin Voltage VGHM-RE PMOS R vs. VGHM Pin Voltage DSON VGH Pin Bias Current vs. VGH Pin Voltage 20126326 VGH-VGHM PMOS R 20126378 VGHM OFF Resistance vs. Temperature 20126380 13 20126377 ...
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LV Quiescent Current vs LDO Dropout Voltage vs. Load Current Op-Amp Source Current vs. AV (Standard Version) www.national.com Voltage LV Quiescent Current vs. Temperature IN IN 20126392 LDO V 20126394 Op-Amp Sink Current vs 20126396 14 ...
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Op-Amp Quiescent Current vs. AV (Standard Version) Op-Amp Offset Voltage vs. Load Current (Standard Version) 1.28MHz, 8.5V Application Boost Startup Waveform = 20Ω 8.5V 3.3V 20µF, R OUT IN OUT LOAD 1) V ...
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Application Boost Startup Waveform V = 8.5V 3.3V 20µF, R OUT IN OUT LOAD 2V/div, DC SHDN 5V/div, DC OUT 1A/div ...
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GPM Transient Waveforms VGH = 20V, VDPM = 3.3V 4.7nF 2.4kΩ, C VGHM 1.2kΩ, VFLK at 50% duty cycle and 30kHz 1) VFLK, 2V/div VGHM, 5V/div 4µs/div Operation ...
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LDO, so the ratio of the feedback re- sistors sets the output voltage according to the following equations: SOFT-START CAPACITOR The LM3311 has a soft-start pin that can be used to limit the inductor inrush current ...
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The current from the power pins goes through the output pin and into the load and feedback loop. The cur- rent exiting the load and feedback loops then must have a return path back to the op-amp power ...
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VGHM pin is driving a purely capacitive load, 4.7nF. The value of resistor R1 is 15kohm 1.1kΩ and R3 is 750Ω. In both transient plots, there FIGURE 3. FIGURE 4. www.national.com In the ...
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INTRODUCTION TO COMPENSATION (BOOST CONVERTER) FIGURE 5. (a) Inductor current. (b) Diode current. The LM3311 is a current mode PWM boost converter. The signal flow of this control scheme has two feedback loops, one that senses switch current and one ...
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C C Output Capacitor ESR Compensation) and 68pF 4.7nF. Refer to the Applications Information section for rec- ommended values for specific circuits and ...
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The size can also be reduced if the input of the regulator is very close to the source output. The size will generally need to be larger for applica- tions where the regulator is ...
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LAYOUT CONSIDERATIONS The input bypass capacitor shown in the typical op- IN erating circuit, must be placed close to the IC. This will reduce copper trace resistance which effects input voltage ripple of the IC. For additional ...
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Application Information FIGURE 6. Evaluation Board Schematic 25 20126323 www.national.com ...
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FIGURE 7. Evaluation Board Layout (top layer) 26 20126324 ...
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FIGURE 8. Evaluation Board Layout (bottom layer) 27 20126325 www.national.com ...
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FIGURE 9. Li-Ion to 8V, 1.28MHz Application 28 20126329 ...
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FIGURE 10 10.5V, 1.28MHz Application Some Recommended Inductors (Others May Be Used) Manufacturer Coilcraft TDK Pulse Sumida CDRH8D28 and CDRH8D43 series Some Recommended Input And Output Capacitors (Others May Be Used) Manufacturer Vishay Sprague 293D, 592D, and 595D ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted LLP-24 Pin Package (SQA) For Ordering, Refer to Ordering Information Table NS Package Number SQA24A 30 ...
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Notes 31 www.national.com ...
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