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This part will be the best compromise between RDSON and QG ideal for top MOSFET. The above parameters represent bare minimum characteristics of MOSFETs. However in connecting Drain Source paths parallel negative effect is that the Gate capacitance Qg also connected low resistance and hence conduction loss sometimes implies high switching | LTspice Tutorial: Part 2 - Analog Circuit Design | LTspice ...

Run this simulation LT with Vin starting . It stays at V until ms then falls to in . Our current sense resistor sets the peak . To select cursors double click on the Vout icon

The coordinates of crosshairs are shown bottom left hand corner screen when box is selected these differential values . uF should suffice. uH. A. Thus the ON time of top MOSFET will be or ns. If the circuit is sensitive to fast current changes on input radio transmitter say connected rail using SEPIC converter buck only mode will give much quieter operation

For a given gate drive coming out of the controller IC lower GateSource capacitance MOSFET quicker will turn . Set the transient analysis to have stop time of ms and click OK. MOSFET Choice Switching and Conduction Losses The MOSFETs present two circuit . RJK Datasheet Output Capacitor Choice In continuous conduction mode the has continual current flowing into from inductor. It is interesting to note that the value of di dt determined ONLY by inductance and voltage across inductor. I designed a V to buck converter where spent ages picking the top FET balance Qg and RDSON only get efficiency of . The switching losses result from current flowing through MOSFET at same time that voltage is across so power generated during turn on and off times . If the input voltage is very close to output duty cycle will be high. Hitting the F key undoes this action