* *Continuous conditioning circuit with a variable capacitor ***** Parameter definition******* * gap closing transducer parameters: initial gap, area .params d0=45e-6 .params S=1e-4 * Mobile electrode sinusoidal motion parameters: amplitude, freq. in Hz .params X0=42e-6 .params f=100 * Permittivity of the vacuum .params eps0=8.85e-12 * Parasitic capacitance in series with the transducer .params Cp=30e-12 *Load resistance .params RL=1 * Bias voltage .params Vbias=40 **************************************** ********* The netlist: * Definition of the variable capacitance Vdisp disp 0 sine ( 0 {X0} {f*2*3.14} 0 0 0 0) Ecvar Cvar 0 value={eps0*S/(d0-V(disp))} * Current generated by the variable capacitor Bi_Cvar C1 0 I=(V(Cvar)*ddt(V(C1))+V(C1)*ddt(V(Cvar))) *parasitic capacitance Cp C1 0 {Cp} * load resistance and bias voltage Rl C1 bias {RL} V0 bias 0 {Vbias} ******Simulator commands * Transient simulation .tran 0 1 0 1E-2 ** step on three values of Rload ** .step param Rl list 1e6 10e6 30e6 ** Measure the power on the load resistance .measure tran LoadPower avg V(C1,bias)*V(C1,bias)/RL ** simulation parameters .options method=gear reltol=1e-6 .end