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LM3524J Datasheet

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LM2524D,LM3524D
LM2524D/LM3524D Regulating Pulse Width Modulator
Literature Number: SNVS766D
Specifications of National Semiconductor LM3524J
Date_code:
04+
Quantity:
200

Summary of Contents

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LM2524D,LM3524D LM2524D/LM3524D Regulating Pulse Width Modulator Literature Number: SNVS766D ...

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... In addition, the LM3524D can now be synchronized external- ly, through pin 3. Also a latch has been added to insure one Connection Diagram Order Number LM2524DN or LM3524DN © 2008 National Semiconductor Corporation 8650 pulse per period even in noisy environments. The LM3524D includes double pulse suppression logic that insures when a shut-down condition is removed the state of the T-flip-flop will change only after the first clock pulse has arrived ...

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Block Diagram www.national.com 2 865001 ...

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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. Supply Voltage Collector Supply Voltage (LM2524D) (LM3524D) Output Current DC (each) Oscillator Charging Current (Pin 7) Electrical Characteristics (Note 1) Symbol Parameter REFERENCE ...

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Symbol Parameter Sawtooth Valley R 5.6k Voltage ERROR-AMP SECTION V Input Offset Voltage I Input Bias Current I Input Offset Current ...

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Symbol Parameter Common Mode Voltage Range V − SHUT DOWN SECTION V High Input V − (Pin 2) Voltage 150 mV I High Input I SD (pin 10) Current OUTPUT ...

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Typical Performance Characteristics Switching Transistor Peak Output Current vs Temperature Maximum & Minimum Duty Cycle Threshold Voltage Output Transistor Emitter Voltage www.national.com Maximum Average Power Dissipation (N, M Packages) 865028 Output Transistor Saturation Voltage 865030 Reference Transistor Peak Output Current ...

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Standby Current vs Voltage Current Limit Sense Voltage Test Circuit Standby Current vs Temperature 865034 865036 7 865035 865004 www.national.com ...

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Functional Description INTERNAL VOLTAGE REGULATOR The LM3524D has an on-chip 5V, 50 mA, short circuit pro- tected voltage regulator. This voltage regulator provides a supply for all internal circuitry of the device and can be used as an external reference. ...

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The output of the amplifier, or input to the pulse width modu- lator, can be overridden easily as its output impedance is very high (Z 5 MΩ). For this reason a DC voltage can be applied O to pin 9 ...

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Typical Applications FIGURE 7. Positive Regulator, Step-Up Basic Configuration (I FIGURE 8. Positive Regulator, Step-Up Boosted Current Configuration www.national.com 865011 80 mA) IN(MAX) 865012 10 ...

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FIGURE 9. Positive Regulator, Step-Down Basic Configuration (I 11 865013 80 mA) IN(MAX) www.national.com ...

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FIGURE 10. Positive Regulator, Step-Down Boosted Current Configuration www.national.com FIGURE 11. Boosted Current Polarity Inverter 12 865014 865015 ...

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BASIC SWITCHING REGULATOR THEORY AND APPLICATIONS The basic circuit of a step-down switching regulator circuit is shown in Figure 12, along with a practical circuit design using the LM3524D in Figure 15. FIGURE 12. Basic Step-Down Switching Regulator FIGURE 13. ...

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Also, see LM1578 data sheet for graphical methods of induc- tor selection. CALCULATING OUTPUT FILTER CAPACITOR C Figure 13 shows L1's current with respect to Q1 times ( the collector of Q1). This curent must flow ...

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Staver Heatsink No. V5- BD344 Q2 2N5023 L1 >40 turns No. 22 wire on Ferroxcube No. K300502 Torroid core. FIGURE 15. 5V, 1 Amp Step-Down Switching Regulator 15 865020 www.national.com ...

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Parameter Output Voltage Switching Frequency Short Circuit Current Limit Load Regulation Line Regulation Efficiency Output Ripple FIGURE 16. 5V, 1 Amp Switching Regulator, Foil Side FIGURE 17. Stuffing Diagram, Component Side www.national.com TABLE 1. Conditions Typical Characteristics V 10V, ...

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THE STEP-UP SWITCHING REGULATOR Figure 18 shows the basic circuit for a step-up switching reg- ulator. In this circuit Q1 is used as a switch to alternately apply V across inductor L1. During the time energy is ...

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In calculating the output capacitor C it can be seen that C o supplies I during t . The voltage change time will be some ΔV ΔV or the output ripple of the regu- c ...

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L1 > 25 turns No. 24 wire on Ferroxcube No. K300502 Toroid core. FIGURE 20. 15V, 0.5A Step-Up Switching Regulator FIGURE 21. Replacing R3/R4 Divider in Figure 20 with Reference Circuit Improves Line Regulation FIGURE 22. Polarity Inverter Provides ...

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Physical Dimensions inches (millimeters) unless otherwise noted www.national.com Molded Surface-Mount Package (M) Order Number LM3524DM NS Package Number M16A 20 ...

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Molded Dual-In-Line Package (N) Order Number LM2524DN or LM3524DN NS Package Number N16E 21 www.national.com ...

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... For more National Semiconductor product information and proven design tools, visit the following Web sites at: Products Amplifiers www.national.com/amplifiers Audio www.national.com/audio Clock Conditioners www.national.com/timing Data Converters www.national.com/adc Displays www.national.com/displays Ethernet www.national.com/ethernet Interface www.national.com/interface LVDS www.national.com/lvds Power Management www.national.com/power Switching Regulators www.national.com/switchers LDOs www ...

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Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should obtain the ...

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