| etantonio |
Posted - 11/12/2005 : 10:30:36 |
Good Morning,
I'm using ADS2004 and looking into the MW_CKts examples I found the project LNA_1GHz_prj, inside it is described the design of a LNA, at the end of all the ideal components of finishedAmp are replaced with "real world" parts, so the questions :
1) When it is necessary to insert a 90 deg microstrip bend ??
The using of this component is just to optimize spaces in the layout ??
2) between any "real world" component it is inserted a microstrip line, this is due to the fact that these components are always connected to other component with a line, or there are other reasons??
Thanks
Antonio |
| Trenton23023 |
Posted - 01/03/2006 : 04:06:59 |
Originally posted by Walt
I mean, if you use an ideal 10nH inductor that resonate for instance at 500Mhz, when you are planning to design a circuit that must operate at 1GHz, what you simulate in the first step differs too much with the simulations outcome from the step n°2the last step consists in the optimization of the circuit with all the layout component considered in the schematic to accomplish to the design specifications. |
At the end, "outcome" will alwasy stay the same as it used to.
|
| Walt |
Posted - 11/12/2005 : 11:37:41 |
Yes, this could be a procedure, but you have to think on what you are going to do... I mean, if you use an ideal 10nH inductor that resonate for instance at 500Mhz, when you are planning to design a circuit that must operate at 1GHz, what you simulate in the first step differs too much with the simulations outcome from the step n°2
the last step consists in the optimization of the circuit with all the layout component considered in the schematic to accomplish to the design specifications |
| etantonio |
Posted - 11/12/2005 : 10:47:31 |
So,
how it is the standard design procedure?
1) design the LNA with lumped elements
2) replace lumped elements with parts from the available library
3) optimize the layout inserting also elements like 90 deg microstrip to arrange the circuit in the space available
Is this the right flow ??
Thanks |
| Walt |
Posted - 11/12/2005 : 10:45:11 |
If I well understood your questions...
1) Whenever you use a 90 deg microstrip bend for layout reasons ;-)
Tipically a 90 deg bend is characterized by a L serie C shunt and L serie T network. So to take into account the effects of these "parasitics" components you have to put the bend component in the schematic
2) You're right, in this way you take into account the effects of the interconnecting transmission lines, as for the previous situation |
