NCP5005GEVB ON Semiconductor, NCP5005GEVB Datasheet
NCP5005GEVB
Specifications of NCP5005GEVB
Related parts for NCP5005GEVB
NCP5005GEVB Summary of contents
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... AND8172/D Understanding the Noise Issue Out of Inductor Based DC-DC Converter Prepared by: Michael Bairanzade ON Semiconductor Abstract Portable applications, such as cellular phones and hand-held computers, have sensitive electronic functions, making any electromagnetic noise a real issue. Even a low power converter can generate noise during transients since the converters operate in the megahertz range ...
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With sense resistor, the dc current through the LEDs with a "10% tolerance over the temperature range. The output voltage will typical) and the 1.0 mF capacitor must be sized ...
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The silicon chip is connected to the external world by means of bonding wires attached to the internal pads. The bonding wires have finite inductance and stray capacitance. In addition, the internal overvoltage protection circuits and PCB trace leads contribute ...
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SPIKE VSPK#1 Assuming the system operates in steady state, let us consider the noise VSPK#1. The current flowing into the NMOS is abruptly switched off and the voltage rises (according to the Lenz's law) until the Schottky diode is forward ...
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SPIKE VSPK#2 The spike is developed during the negative going slope of the output voltage, when the current transfer to the load is completed and the NMOS switch turns on (Figure 5). At this point, the voltage across the Schottky ...
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Discontinuous Mode of Operation Analysis When a chip operates in a fully discontinuous mode, a large peak current takes place in the inductor as depicted in Figure 6. The PWM mode is prone to such a discontinuous cycle. The output ...
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A detailed view of the PWM based chip output voltage shows a non-negligible spike when the inductor current hits the maximum peak value (Figure 7). Basically, this is the same mechanism as the one depicted for the NCP5007 application, and ...
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SPECTRUM ANALYSIS The waveforms captured by an oscilloscope are very useful to evaluate the behavior of a given product, but they don't give information about the EMI performance. At this point, a spectrum analyzer is necessary to characterize the device ...
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AND8172/D Figure 9. PWM Circuit Spectrum Analysis http://onsemi.com 9 ...
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CONCLUSION Since it is not possible to reduce the parasitic inductance to zero (using the micro bump technique could improve but not reduce the inductance to zero nH), and since fast dI/dt is necessary to lower the switching losses into ...
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PSPICE SIMULATIONS The circuit has been simulated prior to run the analysis in the laboratory. The same schematic (Figure 11) has been used to evaluate the configurations. V bat 1 ...
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... Phone: 480-829-7710 or 800-344-3860 Toll Free USA/Canada Fax: 480-829-7709 or 800-344-3867 Toll Free USA/Canada Email: orderlit@onsemi.com AND8172/D sense N. American Technical Support: 800-282-9855 Toll Free USA/Canada Japan: ON Semiconductor, Japan Customer Focus Center 2-9-1 Kamimeguro, Meguro-ku, Tokyo, Japan 153-0051 Phone: 81-3-5773-3850 http://onsemi.com Semiconductor Website: http://onsemi.com Order Literature: http://www ...