LM3224MM-ADJ/NOPB National Semiconductor, LM3224MM-ADJ/NOPB Datasheet
LM3224MM-ADJ/NOPB
Specifications of LM3224MM-ADJ/NOPB
LM3224MM-ADJTR
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LM3224MM-ADJ/NOPB Summary of contents
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... An external soft-start pin allows the user to control the amount of inrush current during start up. The LM3224 is available in a low profile 8-lead MSOP package. Typical Application Circuit © 2005 National Semiconductor Corporation Features n Operating voltage range of 2. 615kHz/1.25MHz pin selectable frequency operation n Over temperature protection ...
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... Connection Diagram Ordering Information Order Number Spec. LM3224MM-ADJ LM3224MMX-ADJ LM3224MM-ADJ NOPB LM3224MMX-ADJ NOPB Pin Descriptions Pin Name SHDN 4 GND FSLCT 8 SS www.national.com Top View 20097604 8-Lead Plastic MSOP NS Package Number MUA08A Package NSC Package Type Drawing MSOP-8 MUA08A 1000 Units, Tape and ...
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Block Diagram General Description The LM3224 utilizes a PWM control scheme to regulate the output voltage over all load conditions. The operation can best be understood referring to the block diagram and Figure 1 of the Operation section. At the ...
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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 (Note 2) V Voltage (Note 3) C SHDN Voltage FSLCT Maximum Junction Temperature Power Dissipation(Note 4) Lead Temperature Electrical Characteristics Specifications in standard type face are for T ture Range ( T = − ...
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Electrical Characteristics Note 5: The human body model is a 100 pF capacitor discharged through a 1.5kΩ resistor into each pin. The machine model is a 200pF capacitor discharged directly into each pin. Note 6: All limits guaranteed at room ...
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Typical Performance Characteristics NMOS R vs. Input Voltage DSON 1.25MHz Non-switching I Q 1.25MHz Switching I vs. Input Voltage Q www.national.com (Continued) 615kHz Non-switching I 20097620 vs. Input Voltage 20097622 20097624 6 vs. Input Voltage Q 20097621 615kHz Switching I ...
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Typical Performance Characteristics 1.25MHz Switching I vs. Temperature Q 1.25MHz Switching Frequency vs. Temperature 1.25MHz Maximum Duty Cycle vs. Temperature (Continued) 615kHz Switching Frequency vs. Temperature 20097626 615kHz Maximum Duty Cycle vs. Temperature 20097628 Switch Current Limit vs. V 20097651 ...
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Typical Performance Characteristics Switch Current Limit vs. Temperature 1.25MHz Efficiency vs. Load Current www.national.com (Continued) Switch Current Limit vs. Temperature 20097652 20097653 8 20097662 ...
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Operation FIGURE 1. Simplified Boost Converter Diagram (a) First Cycle of Operation (b) Second Cycle Of Operation CONTINUOUS CONDUCTION MODE The LM3224 is a current-mode, PWM boost regulator. A boost regulator steps the input voltage higher output ...
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Operation (Continued) INTRODUCTION TO COMPENSATION FIGURE 2. (a) Inductor current. (b) Diode current. The LM3224 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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Operation (Continued) must exceed the switch current limit. Using Schottky diodes with lower forward voltage drop will decrease power dissipa- tion and increase efficiency. DC GAIN AND OPEN-LOOP GAIN Since the control stage of the converter forms a complete feedback ...
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Operation (Continued) where R is the output impedance of the error amplifier, O approximately 900kΩ. Since R is generally much less than does not have much effect on the above equation and O can be neglected ...
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Application Information FIGURE 3. Triple Output TFT Bias (615 kHz operation) TRIPLE OUTPUT TFT BIAS The circuit in Figure 3 shows how the LM3224 can be configured to provide outputs of 8V, −8V, and 23V, conve- nient for biasing TFT ...
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Application Information to the last, there are three diode drops that make the output FIGURE 5. Continuously Operating White LED Flash/Torch Driver www.national.com voltage closer 3xVDIODE (about 22. 0.4V (Continued) forward drop is assumed). FIGURE ...
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Application Information The LM3224 can be configured to drive high current white LEDs for the flash and torch functions of a digital camera, camera phone, or any other similar light source. The flash/ torch can be set up with the ...
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Application Information www.national.com (Continued) FIGURE 6. 1.25MHz, 5V Output FIGURE 7. 1.25MHz, 8V Output 16 20097661 20097663 ...
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Application Information (Continued) FIGURE 8. 1.25MHz, 12V Output FIGURE 9. 1.25MHz, 15V Output 17 20097664 20097665 www.national.com ...
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