yixiusky wrote on May 28th, 2008, 6:53am: thank u very much ^^ I make like this shown in attached picture. Is this ok ? Thank you very much !
I am sorry to ask what's "an additional subtracting unit" ? ^^
Hi,
If you want to make an ideal OTA, then I would suggest that you use the same structure which you would use to do the simplest hand analysis of your OTA:
A VCCS + output resistance in parallel. I would imagine that there is no need to build in the lowpass filters. When you connect the external capacitive
loads to this OTA model, the bandwidth will be automatically set, and will in fact more accurately track the load capacitance than if you plug in an ideal LPF
in between as you have done here. If you have a 2-stage opamp with internal compensation, a similar structural model suffices. In my experience, this is the most
accurate and simple model. You can even set limits on the current of the VCCS to model slewing if you want !!!
Keep it as simple as possible but no simpler...
Regards
Vivek