User`s guide

15
-
8 Mixed Analo
g
/Di
g
ital Simulation
with all primitives appropriately connected to the power supply
nodes.
Table 15-2
summarizes the default node names and values. For
instance, TTL family parts default to 5 volt power supplies at
analog/digital interfaces.
The IPIN attributes default to the same digital power and ground
nodes created by the default power supply. These node
assignments are passed from the part instance to the digital
primitives describing its behavior, thus connecting any digital
primitive affected by an analog connection to the correct power
supply.
Creatin
g
Custom Di
g
ital Power
Supplies
Each digital device model has optional digital power and ground
nodes which provide the means for specifying custom power
supplies.
You can define your own power supplies with voltages different
from the defaults by placing one of the digital power supplies
Table 15-2
Default Digital Power/Ground Pin Connections
Logic
Family
Digital Power/
Ground Pin
Attributes
Default Digital Power/Ground
Nodes
TTL IPIN(PWR)
IPIN(GND)
$G_DPWR (5.0 volts)
$G_DGND (0 volts)
CD4000 IPIN(VDD)
IPIN(VSS)
$G_CD4000_VDD (5 volts)
$G_CD4000_VSS (0 volts)
ECL 10K IPIN(VEE)
IPIN(VCC1)
IPIN(VCC2)
$G_ECL_10K_VEE (-5.2 volts)
$G_ECL_10K_VCC1 (0 volts)
$G_ECL_10K_VCC2 (0 volts)
ECL 100K IPIN(VEE)
IPIN(VCC1)
IPIN(VCC2)
$G_ECL_100K_VEE (-4.5 volts)
$G_ECL_100K_VCC1 (0 volts)
$G_ECL_100K_VCC2 (0 volts)
The default I/O models and
power supply subcircuits are
found in
dig_io.lib. The four
default power supplies provided
in the model library are
DIGIFPWR (TTL),
CD4000_PWR (CD4000 series
CMOS), ECL_10K_PWR (ECL
10K), and ECL_100K_PWR
(ECL 100K).
When creatin
g
custom power
supplies, you can refer to the
power supply definitions in
dig_io.lib for examples of
power supply subcircuit
definitions.