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Lately I've been working on some RF circuits, and for them the two most important parameters of any component is capacitance and inductance. EC doesn't take into account the inductance of components, but accompanies for the capacitance. Well you gotta know what you're dealing with in EC when you design a circuit. So a simple resonance method gives us a good landmark about the rough values of the I/O capacitance of the transistors here in EC. Okay here's some of the measurements I got by substitution in the formula f=1/2пsqrtLC. Both the MOSFETS and the BJT's have the same I/O parameters.
Input capacitance (Gate/Base) - the resonant frequency is ~71MHz and the second known constant is the 1uH inductor, so the capacitance is around 5pF, for resonance at these values.
- Output Capacitance (Drain/Collector) - the resonant frequency is around ~100MHz so the capacitance is 2.5pF
These values fit most VHF transistor values, but mostly for the BJT's. For MOSFETs such values are nearly impossible, since most MOSFETs even very fast ones have gate capacitance of at least a hundred pF, but that's how MOSFETs are designed to work. The gate is like a capacitor switch or something. Anyway keep this in mind when designing fast switching MOSFET schematics here in EC. The input capacitance is unrealistically low and you should add a gate capacitor to ground in reference with the datasheet of the real MOSFET you'll be using.
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