User Guide

Chapter 6 Analog behavioral modeling
178
expression. This is the PSpice internal sweep variable
used in transient analyses. For any analysis other than
transient, TIME = 0. The relevant property settings for this
device are shown below:
EXPR = 15ma*SIN(6.28*10kHz*TIME+V(%IN+,%IN-))
EMULT, GMULT, ESUM, and GSUM
The EMULT and GMULT parts provide output which is
based on the product of two input sources. The ESUM and
GSUM parts provide output which is based on the sum of
two input sources. The complete transfer function may
also include other mathematical expressions.
Example 1
Consider the device in Figure 51. This device computes
the instantaneous power by multiplying the voltage
across pins %IN+ and %IN- by the current through
VSENSE. This device’s behavior is built-in to the
PSPICETEMPLATE property as follows (appears on one
line):
TEMPLATE=E^@REFDES %OUT+ %OUT- VALUE {V(%IN1+,%IN1-)
*V(%IN2+,%IN2-)}
You can use the part editor to change the characteristics of
the template to accommodate additional mathematical
functions, or to change the nature of the transfer function
itself. For example, you may want to create a voltage
divider, rather than a multiplier. This is illustrated in the
following example.
Example 2
Consider the device in Figure 52.
Figure 51 EMULT part example.
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