I am trying to do a very basic transient analysis of a really basic RC circuit but I am getting weird results. I picked the most basic kind of transient simulation I could think of but couldn’t get it to work. I would expect a very basic R-C curve as the capacitor charges up. I get some kind of jagged saw tooth shape.
You will have to understand how transient simulation is working.
In the beginning an operating point is simulated (op), to act as a starting point for the tran simulation.
What does op mean? Open all capacitors, shorten all inductors, put on all voltages, calculate resulting currents and voltages.
What about node A in your circuit? After op it is at 10V.
What happens when transient simulation is running? Nothing, as the equilibrium has been reached already during op.
You have to give starting conditions, starting at 0 V in node A.
The best way to do so is not using a VDC source, but a pulse source with a single step from 0 to 10 V, to really ensure catching the start-up conditions, like V1 B 0 dc 0 pulse (0 10 1u 1u 1u 1 1)
Pulse width and period a far beyond TSTOP (end of simulation time), so you will see only the rising edge of the pulse. Delay time is 1u, just to see the step.