LM2650MX-ADJ National Semiconductor, LM2650MX-ADJ Datasheet
LM2650MX-ADJ
Specifications of LM2650MX-ADJ
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LM2650MX-ADJ Summary of contents
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... Typical Application Converting a Four-Cell Li Ion Battery to 5V © 2000 National Semiconductor Corporation Features n Ultra high efficiencies (95% possible) n High efficiency over milliamperes load range n Synchronous switching of internal NMOS power FETs n Wide input voltage range (4 ...
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... The positive supply rail of the internal 4V regulator. Bypass V IN capacitor. 20 FREQ ADJ: The LM2650 switches at a nominal 90 kHz. Connect a resistor between FREQ ADJ and GND to adjust the frequency up from the nominal. Use the graph under Typical performance Characteristics to select the resistor. 21 SYNC: The synchronization input ...
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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. (All voltages are referenced to the PGND and GND pins.) DC Voltage at PV and Voltage at SD, SLEEP LOGIC and SYNC DC current into SW Junction Temperature ...
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... See Application Notes on thermal management. The LM2650 actively limits its junction temperature to about 170˚C. Note 3: For detailed information on soldering plastic small-outline packages, refer to the Packaging Databook published by National Semiconductor Corporation. Note 4: ESD is applied using the human-body model, a 100pF capacitor discharged through a 1.5k Note 5: A typical is the center of characterization data taken at T Note 6: All limits are guaranteed ...
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Typical Performance Characteristics I vs Input Voltage QSD DS012848 Oscillator Frequency Q DS012848-6 R Low-Side vs Junction DS(on) Temperature DS012848-9 Oscillator Frequency vs Adjusting Resistor DS012848- Input Voltage QS DS012848-4 R Low-Side vs Input Voltage DS(on) ...
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Block Diagrams FIGURE 1. The PWM Circuit with External Components in a Closed Control Loop FIGURE 2. The Hysteretic or Sleep Circuit with External Components in a Closed Control Loop FIGURE 3. The Internal Voltage Regulator and Voltage Reference used ...
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... The 50 ns delay between one switch beginning to turn off and the other switch beginning to turn on prevents the switches from shooting through directly from the input supply to the ground. The PWM circuit drives the pulse stream into the ...
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... The hysteretic loop supports light loads more efficiently because it uses less power to support its own operation; it uses less bias power because it’s a simpler loop having less circuit blocks to bias, and it switches slower incurs lower switching losses. The hysteretic control loop does not switch at a constant frequency ...
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Application Circuits (Continued) TABLE 1. Components for the Typical 90 kHz Application Circuit Input Voltage Applicable Cell Stacks Output Input Capacitor C IN Inductor L1 Output Capacitor C OUT Feedback Resistors R1 and R2 Compensation Components ...
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Application Circuits (Continued) FIGURE 5. An Efficient, 2% Accurate 5V to 3.3V Converter www.national.com 10 DS012848-20 ...
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... NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant ...