Calculates a AC sweep of a circuit using the nodal approach. After the analysis is complete, nodal voltages are saved in circuit and terminals with the aC_ prefix. After this the analysis drops to an interactive shell if the shell global variable is set to True.
An OP analysis is performed first to obtain the Jacobian from nonlinear devices. Convergence parameters for the Newton method are controlled using the global variables in .options.
One plot window is generated for each .plot statement. Use the following request types for this analysis: ac (complex), ac_mag, ac_phase or ac_dB.
AC formulation documented in Nodal Analyses Reference
Example:
.analysis ac start=100. stop=1MEG num=100 log=True
.plot ac_dB 153 151 23
.plot ac_phase 23
Name Default Unit Description log 0 Use logarithmic scale num 50 Number of points in sweep shell 0 Drop to ipython shell after calculation start 1.0 Hz Frequency sweep start value stop 10.0 Hz Frequency sweep stop value
Calculates a DC sweep of a circuit using the nodal approach. After the analysis is complete, nodal voltages are saved in circuit and terminals with the dC_ prefix. After this the analysis drops to an interactive shell if the shell global variable is set to True.
The following parameters can be swept:
- Any device parameter of float type (device name must be specified in this case)
- Global temperature (no device specified): sweep temperature of all devices that do not explicitly have temp set.
Convergence parameters for the Newton method are controlled using the global variables in .options. The type of matrix used in this analysis is controlled by the sparse option. Global options are documented in Global Options and Constants Tables.
One plot window is generated for each .plot statement. Use dc request type for this analysis.
DC analysis formulation is documented in Nodal Analyses Reference, and internal classes and functions used in this analysis are documented in Analyses Utility Classes and Functions.
Examples:
# Device parameter sweep
.analysis dc device=vsin:v1 param=vdc start=-2. stop=2. num=50
# Global temperature sweep
.analysis dc param=temp start=-20C stop=80C
# Some options that affect convergence properties
.options maxiter=300 gyr=1e-5 maxdelta=5.
.plot dc 153 151 23
Name Default Unit Description device Instance name of device to sweep variable num 50 Number of points in sweep param Parameter to sweep shell 0 Drop to ipython shell after calculation start 0.0 (variable) Sweep start value stop 0.0 (variable) Sweep stop value verbose 0 Show iterations for each point
Calculates the DC operating point of a circuit using the nodal approach. After the analysis is complete, nodal voltages are saved in circuit and terminals with the nD_ prefix. After this the analysis drops to an interactive shell if the shell global variable is set to True.
By default the voltage at all external voltages is printed after the analysis is complete. Optionally the operating points of nonlinear elements can be printed.
Convergence parameters for the Newton method are controlled using the global variables in .options. The type of matrix used in this analysis is controlled by the sparse option. Global options are documented in Global Options and Constants Tables.
OP analysis formulation is documented in Nodal Analyses Reference, and internal classes and functions used in this analysis are documented in Analyses Utility Classes and Functions.
Example:
.analysis op intvars=1 shell=1
Name Default Unit Description elemop 0 Print element operating points intvars 0 Print internal element nodal variables shell 0 Drop to ipython shell after calculation
One advantage of using this method over a DC sweep is that no Newton iterations are needed. The following internal functions are tested here:
After completion the analysis drops to an interactive shell if the shell global variable is set to True
Example:
.analysis testdev plot=1 ports_bias = [3V, 3.V, 0V] sweep_port=1 \
start = 0V stop= 3V sweep_num=1000 device = mosekv:m1 \
param = temp param_val = [-10, 27, 50]
Name Default Unit Description device Instance name of device to test param Parameter for outer sweep param_val [] Vector with parameter values to sweep plot 1 Auto-plot currents and charges ports_bias [] V Vector with default values of port voltages shell 0 Drop to ipython shell after calculation start 0.0 V Sweep start value stop 0.0 V Sweep stop value sweep_num 0 Number of points in sweep sweep_port 0 Port number to be swept, starting from zero useAD 1 Use automatic differentiation
Solves nodal equations starting from t=0 to tstop with a fixed time step equal to tstep. Two integration methods are supported: Backwards Euler (im = BE) and trapezoidal (im=trap). Support for frequency-defined elements and time delays is not yet included.
Convergence parameters for the Newton method are controlled using the global variables in .options. The type of matrix used in this analysis is controlled by the sparse option. Global options are documented in Global Options and Constants Tables.
One plot window is generated for each .plot statement. Use tran request type for this analysis. By default, only results for nodes listed in .plot statements are saved. To save all nodal variables set saveall to 1.
Transient analysis formulation is documented in Nodal Analyses Reference, and internal classes and functions used in this analysis are documented in Analyses Utility Classes and Functions.
Example:
.analysis tran tstop=1ms tstep=.01ms im=BE
.plot tran vin vout
Name Default Unit Description im trap Integration method saveall 0 Save all nodal voltages shell 0 Drop to ipython shell after calculation tstep 1e-05 s Time step size tstop 0.001 s Simulation stop time verbose 0 Show iterations for each point