LM3524DM National Semiconductor, LM3524DM Datasheet
LM3524DM
Specifications of LM3524DM
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LM3524DM Summary of contents
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... One pulse per period (noise suppression) ■ Improved max. duty cycle at high frequencies ■ Double pulse suppression ■ Synchronize through pin 3 Top View Order Number LM2524DN or LM3524DN See NS Package Number N16E Order Number LM3524DM See NS Package Number M16A 8650 May 2, 2008 865002 www.national.com ...
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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 T Voltage ERROR-AMP SECTION V Input Offset Voltage I Input Bias Current I Input Offset Current I Compensation V COSI IN(I) Current (Sink) I Compensation ...
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Symbol Parameter Common Mode Voltage Range V − SHUT DOWN SECTION V High Input V SD (Pin 2) Voltage 150 mV I High Input I SD (pin 10) Current OUTPUT SECTION (EACH 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 865034 865036 7 Standby Current vs Temperature 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) 10 865012 ...
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FIGURE 9. Positive Regulator, Step-Down Basic Configuration (I 865013 = 80 mA) IN(MAX) 11 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 www.national.com TABLE 1. Conditions V = 10V 10V 10V IN ...
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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 drawn ...
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In calculating the output capacitor C supplies I during t . The voltage change time will be some ΔV = ΔV or the output ripple of the regu lator. Calculation of C is: o ...
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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 www.national.com inches (millimeters) unless otherwise noted 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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