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2

Years have passed since this problem was reported. If someone else stumbles over this thread, just like me. After hours of trying, I've just made a working simulation with the MCP601. Try: .options cshunt=1e-15 to avoid the convergence problem.


2

The delay can't be zero valued, so when dly > 0 it works just fine. But the whole if() expression needs to be parsed prior to simulation, and when dly = 0, the delay() function is parsed and dly is replaced by its evaluated number, which is zero, and which gives a rightful error. To solve this, make a second variable and replace dly inside the behavioural ...


3

You have no DC path to ground on the AD8513 input. A resistor to ground or whatever other DC reference you want to use will provide that. The bias current of the 8513 is pA or nA over a reasonable temperature range, but it still needs a path. Also the (likely bigger) factor of the DC leakage through a 220uF capacitor needs to be dealt with. The resistor ...


5

You seem to have at least one short. Orcad's schematic editor has the delightful habit of adding shorts here and there, perhaps there are others.


2

No, they're the furthest thing from being unique unless they're just copied. In general SPICE models reflect typical characteristics, to some degree of accuracy. Datasheets offer 'typical' characteristics, sometimes, but the min/max is usually what we are most interested in. A jellybean transistor eg. 2N3904 from manufacturer A may meet all the min/max JEDEC ...


1

ngspice and LTSPICE offer a large variety of MOS models, from simple to complex. ngspice supports the BSIM3 and BSIM4 series of models, similar to Spectre or HSPICE, for simulations down to the 22 nm node. It has been tested and used with (proprietary) PDKs from TSMC or X-Fab. ngspice has been chosen by the Google/SkyWater OpenSource PDK project as a ...


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