Theme: Simulation
Help, my simulation won't start! What can I do?
Error messages are reported by the simulation kernel, but they are not useful.
There are many ways to create a circuit incorrectly:
Power supply the wrong way round. One user had applied +12V with a constant voltage source on one side of an OpAmp and -12V on the other side. As the positive pole of the source was then pointing towards the component, he additionally rotated the negative source by 180°. The OpAmp is then connected twice to +12V and therefore has no supply, because minus times minus equals plus.
Astable multivibrator does not oscillate. If you create an astable multivibrator or a similar circuit consisting of two or more symmetrical circuit parts, it will in nature start to oscillate immediately. This is because the components you have purchased are not really exactly identical. In the simulator it is different: e.g. 10k is 10k everywhere. The simulator cannot decide which channel should start and goes into a twilight state. If you now change a component of a channel imperceptibly, e.g. 10.01k, then it starts oscillating.
Renaming a signal produces a strange error message. In the simulator, you can also create probes and "Initial conditions" in the "Advanced" tab. Of course, you may no longer use the old signal name that no longer exists.
You can also take a look at Simulation Pitfalls.
