LM3524DN National Semiconductor, LM3524DN Datasheet
LM3524DN
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LM3524DN Summary of contents
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... Wide common mode input range for error-amp n One pulse per period (noise suppression) n Improved max. duty cycle at high frequencies n Double pulse suppression n Synchronize through pin 3 00865002 Top View Order Number LM2524DN or LM3524DN See NS Package Number N16E Order Number LM3524DM See NS Package Number M16A DS008650 March 2005 www.national.com ...
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Block Diagram www.national.com 2 00865001 ...
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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 SECTION ...
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Electrical Characteristics (Note 1) Symbol Parameter Sawtooth Valley R = 5.6k Voltage ERROR-AMP SECTION V Input Offset Voltage I Input Bias Current I Input Offset Current I Compensation V ...
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Electrical Characteristics (Note 1) Symbol Parameter TC-V Sense Voltage T.C. sense 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 ...
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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) 00865028 00865030 Reference Transistor Peak Output Current 00865032 6 00865029 Output ...
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Typical Performance Characteristics Standby Current vs Voltage Current Limit Sense Voltage Test Circuit (Continued) 00865034 00865036 7 Standby Current vs Temperature 00865035 00865004 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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Functional Description The output of the amplifier, or input to the pulse width modu- lator, can be overridden easily as its output impedance MΩ). For this reason a DC voltage can be very high (Z O applied ...
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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 00865011 = 80 mA) IN(MAX) 00865012 10 ...
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Typical Applications (Continued) FIGURE 9. Positive Regulator, Step-Down Basic Configuration (I 00865013 = 80 mA) IN(MAX) 11 www.national.com ...
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Typical Applications FIGURE 10. Positive Regulator, Step-Down Boosted Current Configuration www.national.com (Continued) FIGURE 11. Boosted Current Polarity Inverter 12 00865014 00865015 ...
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Typical Applications (Continued) 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 ...
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Typical Applications where Henrys f is switching frequency in Hz Also, see LM1578 data sheet for graphical methods of in- ductor selection. CALCULATING OUTPUT FILTER CAPACITOR C Figure 13 shows L1’s current with respect to Q1’s t ...
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Typical Applications (Continued) *Mounted to Staver Heatsink No. V5- BD344 Q2 = 2N5023 > turns No. 22 wire on Ferroxcube No. K300502 Torroid core. FIGURE 15. 5V, 1 Amp Step-Down Switching Regulator 15 00865020 www.national.com ...
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Typical Applications 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 www.national.com (Continued) TABLE 1. Conditions V = 10V ...
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Typical Applications (Continued) THE STEP-UP SWITCHING REGULATOR Figure 18 shows the basic circuit for a step-up switching regulator. In this circuit Q1 is used as a switch to alternately apply V across inductor L1. During the time and ...
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Typical Applications This equation shows that the input, or inductor, current is larger than the output current by the factor ( Since this factor is the same as the relation between can also be ...
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Typical Applications (Continued) In calculating the output capacitor C it can be seen that C o supplies I during t . The voltage change time will be some ∆V = ∆V or the output ripple of ...
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Typical Applications > turns No. 24 wire on Ferroxcube No. K300502 Toroid core. FIGURE 21. Replacing R3/R4 Divider in Figure 20 with Reference Circuit Improves Line Regulation FIGURE 22. Polarity Inverter Provides Auxiliary −15V Unregulated Output from ...
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Physical Dimensions inches (millimeters) unless otherwise noted Molded Surface-Mount Package (M) Order Number LM3524DM NS Package Number M16A 21 www.national.com ...
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... Deutsch Tel: +49 (0) 69 9508 6208 English www.national.com Français Tel: +33 ( 8790 Molded Dual-In-Line Package (N) Order Number LM2524DN or LM3524DN NS Package Number N16E 2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system affect its safety or effectiveness ...