Felis_Silvestris
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ads momentum optimization
Hello,
I have been using the optimization feature in ADS (for Momentum). I followed one of the examples (a coupler in the documentation) to set up my own optimization.
In the optimization that I use I have several traces changing length as parameters of optimization. The problem that I have experienced is that the traces “grow” in the wrong direction and will touch other traces that should not be touching.
Here’s the odd thing.
I checked for this potential problem before I began the optimization. I checked by changing the component parameter values while in the layout window to see that my traces “grew” in the correct direction. They did. That is to say while changing parameters values to witness what direction my traces would grow I observed that no traces collided with each other.
Unfortunately, when I ran the optimization at the schematic level the traces grew into each other (the layout created with parameters was used as a subcircuit for the schematic).
I’m using ordinary microstrip traces, “TEE” parts and open stubs.
I can draw diagrams and whatnot if anyone wants a clearer picture if the problem I’m experiencing.
David
Added after 12 minutes:
To be more specific, I have a footprint for a microwave transistor effectively drawn in momentum. Matching networks for the transistor are attached to the footprint. While optimizing it is important that the spacing between pads where the transistor pins connect remain at a fixed distance. The problem I encounter is that these pads move, only when optimizing at the schematic level. It seems that I can go into the layout window and change parameters without altering the pad/pin spacing for the transistor, but as soon as I use the layout as a subcircuit and try to optimize at the schematic level the pads move into each other.
Hello,
I have been using the optimization feature in ADS (for Momentum). I followed one of the examples (a coupler in the documentation) to set up my own optimization.
In the optimization that I use I have several traces changing length as parameters of optimization. The problem that I have experienced is that the traces “grow” in the wrong direction and will touch other traces that should not be touching.
Here’s the odd thing.
I checked for this potential problem before I began the optimization. I checked by changing the component parameter values while in the layout window to see that my traces “grew” in the correct direction. They did. That is to say while changing parameters values to witness what direction my traces would grow I observed that no traces collided with each other.
Unfortunately, when I ran the optimization at the schematic level the traces grew into each other (the layout created with parameters was used as a subcircuit for the schematic).
I’m using ordinary microstrip traces, “TEE” parts and open stubs.
I can draw diagrams and whatnot if anyone wants a clearer picture if the problem I’m experiencing.
David
Added after 12 minutes:
To be more specific, I have a footprint for a microwave transistor effectively drawn in momentum. Matching networks for the transistor are attached to the footprint. While optimizing it is important that the spacing between pads where the transistor pins connect remain at a fixed distance. The problem I encounter is that these pads move, only when optimizing at the schematic level. It seems that I can go into the layout window and change parameters without altering the pad/pin spacing for the transistor, but as soon as I use the layout as a subcircuit and try to optimize at the schematic level the pads move into each other.
