The Source Physical Button: Update Electrical From Physical

The Source Physical button in the Extract Menu will update the electrical part of a design from parameters extracted from the physical part. The command works by writing a temporary SPICE file from the physical database, then updating the electrical database from the SPICE file. When the Source Physical button is pressed, a small pop-up appears, which is similar to the pop-up seen with the Source SPICE command, but has no text entry area, and has an additional Depth choice menu which sets the depth into the hierarchy to process. The Go button initiates the operation.

Node name mapping is turned on after the operation completes. Since a schematic produced in this way has every node name defined by a terminal, using the defined names, which correspond to the physical group numbers, is convenient.

The first three check boxes have similar functions as in the Source SPICE command. The remaining check box enables inclusion of wire-net capacitors.

all devs
If set, all devices in the cell will be considered for updating If not set, only the devices that have names that were set explicitly by the user (by applying a name property) are updated.

create
If set, missing devices are created. If not set, only the properties of existing devices are updated.

clear
If set, the electrical part of a cell is cleared before updating. This implies create.

include wire cap
If set, capacitors that represent routing net capacitance will be updated, or created if they don't exist and create is set. These capacitors are given a special name prefix ``C@NET'' which has significance to Xic, i.e., it identifies them as routing capacitances. The capacitors are added between the wire nets and ground. In order for wire capacitance to be computed, the Capacitance keyword must be supplied in the technology file for the routing layers.

ignore labels
From some tools, cell terminals may be indicated by the presence of a label on a Routing layer, positioned such that the label reference point touches an object on the same layer. Such labels, if found, will be used to generate a terminal list for the top-level cell in the extracted hierarchy, if the existing electrical cell contains no terminals (or the electrical cell doesn't exist). If this box is checked, such labels will always be ignored.

Each of the option buttons has a corresponding !set variable. If the variable is changed while the pop-up is visible, the pop-up will be updated. Conversely, changing the state of the option buttons will set or unset the corresponding variables. The pop-up check box will be checked if the corresponding variable is set, unless the variable name has a ``No'' prefix, in which case the logic is reversed. The names of the corresponding variables are given in the table below.

all devs	NoExsetAllDevs
create	NoExsetCreate
clear	ExsetClear
include wire cap	ExsetIncludeWireCap
ignore labels	ExsetNoLabels