Parasitic Extracted Capacitors: Coordinates

[hamidrezah]

Hi all Cadence experts:

When you extract parasitic capacitors from a layout, you will get a
coordinate (x and y pair) associated with each capacitor on the
extracted view.

What do these coordinates mean? Are they the actual physical location
(on the layout) where the capacitance actually occurs and measured by
Cadence?

The reason I am asking this is because the nets connected to the pins
of the capacitors can span anywhere across the layout. I need to make
sure the coordinates really point to the location where Cadence senses
and measures the capacitance and not some random location along the
associated nets.

Many thanks for your hint and/or clarification.

Kind regards,

Hrh

P.S. I am using QRC and Cadence 6.1.5

 

[Andrew Beckett]

hamidrezah wrote, on 11/15/11 11:41:

Hi all Cadence experts:

When you extract parasitic capacitors from a layout, you will get a
coordinate (x and y pair) associated with each capacitor on the
extracted view.

What do these coordinates mean? Are they the actual physical location
(on the layout) where the capacitance actually occurs and measured by
Cadence?

The reason I am asking this is because the nets connected to the pins
of the capacitors can span anywhere across the layout. I need to make
sure the coordinates really point to the location where Cadence senses
and measures the capacitance and not some random location along the
associated nets.

Many thanks for your hint and/or clarification.

Kind regards,

Hrh

P.S. I am using QRC and Cadence 6.1.5

When the extracted view is created, it should place the parasitic component in
the region where the parasitic arises from.

Note however that if you are using the RC reduction options, that's much harder
(if not impossible) to do... (I've not really experimented, but it no longer has
a one to one correspondence with the geometries in the layout).

Andrew.