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Vxxxx n+ n [[DC] dcvalue] [DCOP] [INFCAP] [AC magnitude [phase]] 
[transient_spec] 
N+  Positive node 
N  Negative node 
DCOP  If this is specified, the voltage source will only be active during the DC operating point solution. In other analyses, it will behave like an open circuit. This is an effective method of creating a 'hard' initial condition. See Alternative Initial Condition Implementations for an example. 
INFCAP  If specified, the voltage source will behave as an infinite capacitor. During the DC operating point solution it will behave like an open circuit. In the subsequent analysis, it will behave like a voltage source with a value equal to the solution found during the operating point. Note that the device is inactive for DC sweeps  as all capacitors are. 
dcvalue  Value of source for dc operating point analysis 
magnitude  AC magnitude for AC sweep analysis. 
phase  phase for AC sweep analysis 
transient_spec  Specification for time varying source as described in the following table. 
Type  Description 

PULSE  Pulse source. Also generates, ramps, sawtooths and triangles 
PWL  Piece wise linear source. Can create any waveform 
PWLFILE  As PWL but get definition from a file 
SIN  Sine wave 
EXP  Exponential signal 
SFFM  Single frequency FM 
NOISE  Real time noise source 
PULSE ( v1 v2 [td [tr [tf [pw [per ]]]]] ) 
Where:
Name  Description  Default 

v1  Initial value (V,A)  Compulsory 
v2  Pulsed value (V,A)  Compulsory 
td  Delay time (S)  Default if omitted = 0 
tr  Rise time (S)  Default if omitted, negative or zero = Time step^{a} 
tf  Fall time (S)  Default if omitted, negative or zero = Time step 
pw  Pulse width (S)  Default if omitted or negative = Stop time^{b} 
per  Period (S)  Default if omitted, negative or zero = Stop time 
a.  Time step is set up by the .TRAN simulator statement which defines a transient analysis. Refer to .TRAN. 
b.  Stop time refers to the end time of the transient analysis. 
SIMetrix deviates from standard SPICE in the action taken for a pulse width of zero. Standard SPICE treats a zero pulse width as if it had been omitted and changes it to the stop time. In SIMetrix a zero pulse width means just that.
Both the above examples give a pulse lasting 5$\mu$S with a period of 10$\mu$S, rise and fall times of 100nS and a delay of 0. The voltage source has a 0V base line and a pulse of 5V while the current source has a 0mA base line and a pulse of 1mA.
PWL ( t1 v1 [t2 v2 [t3 v3 [... ]]] ) 
Each pair of values (ti vi) specifies that the value of the source is vi at time = ti. The value of the source at intermediate values of time is determined by using linear interpolation on the input values.
Although the example given below is for a voltage source, the PWL stimulus may be used for current sources as well.
Gives:
PWLFILE filename 
This performs the same function as the normal piece wise linear source except that the values are read from a file named filename.
The file contains a list of time voltage pairs in text form separated by any whitespace character (space, tab, new line). It is not necessary to add the '+' continuation character for new lines but they will be ignored if they are included. Any nonnumeric data contained in the file will also be ignored.
The PWLFILE source is considerably more efficient at reading large PWL definitions than the standard PWL source. Consequently it is recommended that all PWL definitions with more than 200 points are defined in this way.
The data output by Show /file is directly compatible with the PWLFILE source making it possible to save the output of one simulation and use it as a stimulus for another. It is recommended, however, that the results are first interpolated to evenly spaced points using the Interp() function.
The use of engineering suffixes (e.g. k, m, p etc.) is not supported by PWLFILE.
The PWLFILE source is a feature of SIMetrix and does not form part of standard SPICE.
Note, you can use the simulator statements .FILE and .ENDF to define the contents of the file. E.g.
Vpwl1 N1 N2 PWLFILE pwlSource 
... 
.FILE pwlSource 
... 
... 
.ENDF 
This will be read in much more efficiently than the standard PWL and is recommended for large definitions. See .FILE and .ENDF.
SIN[E] ( vo va [freq [delay [theta [ phase]]]] ) 
Where:
Name  Description  Default 

vo  Offset (V,A)  Compulsory 
va  Peak (V,A)  Compulsory 
freq  Frequency (Hz)  Default if omitted or zero= 1/Stop time^{a} 
delay  Delay (seconds)  Default if omitted = 0 
theta  Damping factor (1/seconds)  Default if omitted = 0 
phase  Phase in degrees  Default if omitted = 0 
a. Stop time refers to the end time of the transient analysis. 
The shape of the waveform is described by:
0 to delay:  vo 
delay to Stop time  $vo + va \cdot \text{e}^{(t\textit{delay})..\textit{theta}} \cdot \sin(2\pi(\textit{freq} \cdot (t  \textit{delay}) + \textit{phase}/360))$ 
Gives output of:
EXP ( v1 v2 [td1 [tau1 [td2 [tau2 ]]]] ) 
Where:
Name  Description  Default 

v1  Initial value (V,A)  Compulsory 
v2  Pulsed value (V,A)  Compulsory 
td1  Rise delay time  Default if omitted or zero: 0 
tau1  Rise time constant  Default if omitted or zero: Time step^{a} 
td2  Fall delay time  Default if omitted or zero: td1 + Time step 
tau2  Fall time constant  Default if omitted or zero: Time step 
a.  Time step is set up by the .TRAN simulator directive which defines a transient analysis. Refer to .TRAN. 
Defined by:
td1 to td2:  $v1 + (v2  v1). [ 1  \text{e}^{(ttd1)/tau1}]$ 
td2 to stop time:  $v1 + (v2  v1). [ 1  \text{e}^{(ttd1)/tau1}] + v1 + (v2  v1). [ 1  \text{e}^{(ttd2)/tau2}]$ 
SFFM ( vo va [fc [mdi [fs ]]] ) 
Where:
Name  Description  Default 

vo  Offset (V,A)  Compulsory 
va  Amplitude (V,A)  Compulsory 
fc  Carrier frequency (Hz)  Default if omitted or zero = 1/Stop time^{a} 
mdi  Modulation index  Default if omitted = 0 
fs  Signal frequency (Hz)  Default if omitted or zero = 1/Stop time 
a.  Stop time refers to the end time of the transient analysis. 
Defined by: $vo + va\cdot\sin[2\pi\cdot \textit{fc}\cdot t + \textit{mdi}\cdot\sin(2\pi\cdot\textit{fs}\cdot t)]$
noise interval rms_value [start_time [stop_time]] 
Source generates a random value at interval with distribution such that spectrum of signal generated is approximately flat up to frequency equal to 1/(2*interval). Amplitude of noise is rms_value volts. start_time and stop_time provide a means of specifying a time window over which the source is enabled. Outside this time window, the source will be zero. If stop_time is omitted or zero a value of infinity will be assumed.
PWLS [TIME_SCALE_FACTOR=time_factor] [VALUE_SCALE_FACTOR=value_factor] 
pwls_spec [ pwls_spec ... ] 
time_factor  Scales all time values in definition by time_factor  
value_factor  Scales all magnitude values by value_factor  
pwls_spec 
may be one of the following:

Name  Description  Default  Compulsory 

FREQ  Frequency  N/A  Yes 
PEAK  Peak value of sine  1.0  No 
OFFSET  Offset  0.0  No 
DELAY  Delay before sine starts.  0.0  No 
PHASE  Phase  0.0  No 
CYCLES  Number of cycles. Use 1.0 for infinity  1.0  No 
MINPOINTS  Minimum number of timesteps used per cycle  13  No 
RAMP  Frequency ramp factor  0.0  No 
if t>0 OR DELAY<0 
PEAK * SIN(f*$2\pi$*t+PHASE*$\pi$/180) + OFFSET 
else 
PEAK * SIN(PHASE*$\pi$/180) + OFFSET 
Where:
Name  Description  Default  Compulsory 

V0  Offset  0  No 
V1  Positive pulse value  1.0  No 
V2  Negative pules value  1.0  No 
RISE  Rise time i.e time to change from V2 to V1  PERIOD/1000  No 
FALL  Fall time i.e time to change from V1 to V2  PERIOD/1000  No 
WIDTH  Positive pulse width  (PERIODRISEFALL)/2  No 
PERIOD  Period  N/A  Yes 
DELAY  Delay before start  0  No 
CYCLES  Number of complete cycles. 1 means infinity  1  No 
