[@Tingsu_2014TEDI]. The equation solver, as well as the the large amount of calculations involved in obtaining the nonlinear coefficients and characteristics of the MTJ STO, make the transient simulation time-consuming. For most of the analyses, none of the parameters in the effective field change for a single run, so that all the heavy calculations can be executed in the *initial step* event in order to improve the efficiency of the simulation. The *initial step* event is pre-defined in Verilog-A and called on the first point of a simulation. Therefore, in these cases, all the coefficients, parameters and characteristics are computed only once in the entire simulation.

Accurate phase generation
-------------------------

In order to generate the time domain signal, which includes all the characteristics of the MTJ STOs, the output of the model should comprise of both RF and DC terms, implemented in Verilog-A as\

  $V$(MTJ\_STO, GND) &lt;+ $V_\text{RF}+V_\text{DC};$
  -----------------------------------------------------

\
 \
where $V_\text{DC}$ is the DC voltage across the MTJ STO and is a function of the effective field angle, as detailed in [@Tingsu_2014TEDI], and $V_\text{RF}$ can be derived based on Eq.(2) and Eq.(11) in [@Tingsu_2014TEDI], written in Verilog-A as\

  $V_\text{RF}=R_\text{prec}\cdot I_\text{DC} \cdot \cos({\omega_0}\cdot \textdollar abstime+\varphi(t));$
  ----------------------------------------------------------------------------------------------------------

\
 \
where 