Micro-Cap v7.1.6 / RM
.PDFPulse source
Schematic format
PART attribute <name>
Examples
P1
MODEL attribute <model name>
Example
RAMP
The PULSE source is similar to the SPICE PULSE independent voltage source, except that it uses a model statement and its timing values are defined with respect to T=0.
Model statement forms
.MODEL <model name> PUL ([model parameters])
Example
.MODEL STEP PUL (VZERO=.5 VONE=4.5 P1=10n P2=20n P3=100n
+ P4=110n P5=500n)
Model parameters |
|
|
|
Name |
Parameter |
Units |
Default |
VZERO |
Zero level |
V |
0.0 |
VONE |
One level |
V |
5.0 |
P1 |
Time delay to leading edge |
S |
1.0E-7 |
P2 |
Time delay to one-level |
S |
1.1E-7 |
P3 |
Time delay to trailing edge |
S |
5.0E-7 |
P4 |
Time delay to zero level |
S |
5.1E-7 |
P5 |
Repetition period |
S |
1.0E-6 |
458 Chapter 22: Analog Devices
Resistor
SPICE format
Syntax
R<name> <plus> <minus> [model name] <value> [TC=<tc1>[,<tc2>]]
Examples
R1 2 3 50
R2 7 8 10K
<plus> and <minus> are the positive and negative node numbers. The polarity references are used only for plotting or printing the voltage across, V(RX), and the current through, I(RX), the resistor.
Schematic format
PART attribute <name>
Examples
R5
CARBON5
VALUE attribute
<value> [TC=<tc1>[,<tc2>]]
Examples 50
10K
50K*(1+V(6)/100)
FREQ attribute <fexpr>
Examples 2K+10*(1+F/1e9)
MODEL attribute [model name]
Example
RMOD
460 Chapter 22: Analog Devices
If [model name] is used and TCE is not specified, <value> is multiplied by a temperature factor, TF.
TF = 1+TC1•(T-Tnom)+TC2•(T-Tnom)2
TC1 is the linear temperature coefficient and is sometimes given in data sheets as parts per million per degree C. To convert ppm specs to TC1 divide by 1E6. For example, a spec of 3000 ppm/degree C would produce a TC1 value of 3E-3.
If [model name] is used and TCE is specified, <value> is multiplied by a temperature factor, TF.
TF = 1.01TCE•(T-Tnom)
If both [model name] and [TC=<tc1>[,<tc2>]] are specified, [TC=<tc1>[,<tc2>]] takes precedence.
T is the device operating temperature and Tnom is the temperature at which the nominal resistance was measured. T is set to the analysis temperature from the Analysis Limits dialog box. TNOM is determined by the Global Settings TNOM value, which can be overridden with a .OPTIONS statement. T and Tnom may be changed for each model by specifying values for T_MEASURED, T_ABS, T_REL_GLOBAL, andT_REL_LOCAL. See the .MODEL command for more on how device operating temperatures and Tnom temperatures are calculated.
Monte Carlo effects
LOT and DEV Monte Carlo tolerances, available only when [model name] is used, are obtained from the model statement. They are expressed as either a percentage or as an absolute value and are available for all of the model parameters except the T_parameters. Both forms are converted to an equivalent tolerance percentage and produce their effect by increasing or decreasing the Monte Carlo factor, MF, which ultimately multiplies the final value.
MF = 1 ± tolerance percentage /100
If tolerance percentage is zero or Monte Carlo is not in use, then the MF factor is set to 1.0 and has no effect on the final value.
The final resistance, rvalue, is calculated as follows:
rvalue = <value> * R * TF * MF
462 Chapter 22: Analog Devices
S_Port ( S-Parameter two-port )
Schematic format
PART attribute <name>
Example
SP1
FILE attribute <file name>
The FILE attribute specifies the path and name of the S-parameter file.
Example
E:\mc7\data\Gg10v20m.s2p
The S_PORT source provides a way of modeling devices using S-parameters. Typically these are provided by RF suppliers in a text file as a table of values for S11, S12, S21, and S22. The file typically looks like this:
!SIEMENS Small Signal Semiconductors
!BFG194
!Si PNP RF Bipolar Junction Transistor in SOT223
! VCE = -10 V |
IC = -20 mA |
|
|
|
||||
! Common Emitter S-Parameters: |
August 1996 |
|||||||
# GHz S MA R 50 |
|
|
|
|
|
|||
! f |
S11 |
|
S21 |
S12 |
S22 |
|
|
|
! GHz |
MAG |
ANG |
MAG ANG |
MAG ANG |
MAG ANG |
|||
0.010 |
0.3302 |
|
-25.4 35.370 169.9 0.0053 |
85.3 |
0.9077 |
-10.0 |
||
0.020 |
0.3471 |
|
-48.2 33.679 161.6 0.0108 |
77.5 |
0.8815 |
-19.8 |
||
0.050 |
0.4525 |
|
-95.0 27.726 139.2 0.0226 |
61.4 |
0.7258 |
-43.7 |
||
0.100 |
0.5462 -131.5 19.023 118.7 0.0332 |
52.2 0.5077 -68.7 |
||||||
0.150 |
0.5723 -149.4 13.754 106.4 0.0394 |
49.1 0.3795 -84.8 |
||||||
0.200 |
0.5925 |
-159.8 10.787 |
99.1 0.0443 |
50.1 |
0.3068 |
-95.0 |
||
0.250 |
0.6023 |
-167.0 |
8.757 |
93.4 0.0497 |
51.2 0.2581 -104.8 |
|||
0.300 |
0.6089 |
-172.2 7.393 89.0 0.0552 |
52.4 0.2298 -112.2 |
|||||
0.400 |
0.6166 |
|
179.7 |
5.617 |
82.1 0.0661 |
54.2 0.1930 -125.5 |
||
... |
|
|
|
|
|
|
|
|
464 Chapter 22: Analog Devices
S (Voltage-controlled switch)
SPICE format
S<name> <plus output node> <minus output node> +<plus controlling node> <minus controlling node> +<model name>
Example
S1 10 20 30 40 RELAMOD
Schematic format
PART attribute <name>
Example
S1
MODEL attribute <model name>
Example
RELAY
This four-terminal voltage-controlled switch is controlled by the voltage across the two input nodes. The switch impedance is calculated from the input voltage and impressed across the output nodes.
RON and ROFF must be greater than zero and less than 1/Gmin.
A 1/Gmin resistor is placed between the controlling nodes to avoid floating nodes.
Do not make the ratio ROFF/RON larger than about 15 decades. The 15 digits of precision used by the simulator can not make meaningful use of a spread greater than 15 in the ratio.
Do not make the transition region, VON-VOFF, too small as this will cause an excessive number of time points required to cross the region. The smallest allowed values for VON-VOFF is (RELTOL•(max(VON,VOFF))+VNTOL).
Model statement forms
.MODEL <model name> VSWITCH ([model parameters])
466 Chapter 22: Analog Devices