...under perpetual construction.
Here you can find some of the circuits I have built in the past, in particulare a 12-bit and 18-bit parallel port analog-to-digital converters with complete schematics and C source code for Linux
A simple analog-to-digital converter that interfaces to a PC parallel port and providing 12 bit of resolution, with four differential input channels. Actual conversion throughput is about 2.5 ksamples/s
A high-resolution ADC : it can provide up to 18 bits plus sign, at 16 samples/s, with four differential or eight single-ended input channels.
Brief overview on how to extract a model for the capacitance-vs-voltage curve of a varactor diode, starting with the graps on the component datasheet.
How to extract a (small-signal) LDMOS model, starting from the device S-parameters, with some examples for common high-frequency LDMOS.