Multiplier parameter for a subcircuit

Hello everyone,

I was wondering if we can define a parameter M to have several subcircuit in parallel. This is very needed in FET models. More specifically, I have modeled a FET as a subcircuit and now want to have several of them in parallel without having to copy and paste.

Thanks for the help in advance

You can do it with array of components. Consider that there is no instance parameter in .subckt SPICE syntax, you have to do it by repeating the subckt device in netlist with array in schematic.

This is a well-known method, but it significantly complicates the scheme. I’ve come up with a better way. I implemented it in LTspice. This can be easily done in Qspice. I made a current multiplier. This is a two-pole terminal, the currents at the terminals of which differ by M times. M is the number of parallel devices. The complexity of the scheme is insignificant.