Controlling Virtuoso schematic inputs with Digital Vector File

The utilization of a Vector File makes controlling multiple input and output signals independently possible. Its implementation is important for a variety of circuits which need different pulses at specific times, relieving the effort to manage PWL voltage sources at schematic.

Note: comments begins with “;” character

radix 1 1 4 4
; radix specifies the number of ports and number of bits for each port,
; the base number is also specified ( from binary '1' to hexadecimal '4' )

io i i i i

; io defines the state of each port, as input "i", output "o"
; or bidirectional "b"
vname Primeiro_Sinal Segundo_Sinal Terceiro_Sinal[0:3] Quarto_Sinal,Quinto_Sinal,Sexto_Sinal,Setimo_Sinal

; vname sets the name of each port

tunit 1ns

; tunit configures the time unit of simulation

trise 1ps
; trise defines the rise time of each vector

tfall 1ps
; tfall defines fall time of each vector

vih 5.0
; vih defines logical '1' voltage

vil 0.0
; vil defines logical '0' voltage
period 10.0

; period determines the time interval between each vector step, the
; number is multiplied by the previously time unit set

idelay 5 0 1 1 0

; idelay inserts a delay at the selected ports multiplied by the time unit

; The next lines will define the states of each port as the
; transient simulation happens, each line represents a time step

; The binary number can be represented with 0 or 1, and the
; hexadecimals with 0-F

0 0 0 0 ; All signals initially set to 0
1 0 F F ; First signal with a logical '1', second with a logical '0' , the other ones set to a logical '1'
0 1 C C ; And goes on
1 0 A A
1 1 3 3

The ports declaration and manipulation are indented by its position from left to right.

To the visualization of the developed signals, it is necessary to open a schematic on Virtuoso and open: “Analog Environment->Setup->Simulation Files”, inserting the file path on the “Vector File” field.

After the simulation, the signals can be seen on results browser



After the simulation, the signals can be seen on results browser
radix 1 1

io i i

vname A B ; schematic input ports 

tunit 1ns

trise 1ps

tfall 1ps

vih 5.0

vil 0.0

period 10.0

0 0
0 1
1 0
1 1
1 0
0 1
0 0 ; 70ns in total





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