Any Mentor Graphics expert here??

[twinkle81]

I have an op amp and assuming its working fine.

The op amp's supply voltages Vdd and Vss is ideally fixed and a sine signal is pump into one of its input. I can get a fine output for a transient response.

But when i try to ramp of the supply voltages (i.e Vss = 0V to -1V). By right, i should still see some sort of signal at the output, however, what i got at the output is always the Vss decreasing magnitude wrt to time.

It doesn't make sense. So i am guessing is there a problem with the software? Or is there someway to monitor the output while changing the supply voltages wrt to time.

P/S when i ran a transient simulation with discrete values of supply voltages(i.e multiple runs at Vss = 0.2, 0.4, 0.6 etc, the output of the op amp still has sensible results.

Please help!

 

[Humungus]

I have been working with Eldo since a while, and I've seen strange behaviors, but that is just non sense.

Something must be wrong with your netlist. To which nodes is your sinus input signal connected?

Post the netlist and if possible an image of your strange simulation result and I'll tell you.