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Diffstat (limited to 'Windows/spice/examples/control_structs/s-param.cir')
| -rw-r--r-- | Windows/spice/examples/control_structs/s-param.cir | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/Windows/spice/examples/control_structs/s-param.cir b/Windows/spice/examples/control_structs/s-param.cir new file mode 100644 index 00000000..bff277f7 --- /dev/null +++ b/Windows/spice/examples/control_structs/s-param.cir @@ -0,0 +1,120 @@ +Test for Scattering Parameters +** Two ports +** Examples: Bipolar, Tschebyschef, RC + +.param Rbase=50 Vbias_in=0 Vbias_out=0 + +*** The two-port circuit: +** port 1: in 0 +** port 2: out 0 +** Bias on both ports through resistor Rbase (to obtain operating point) + +** Example RF Bipolar mrf5711 +** VCE 1 V, IE = 5mA +** QXXXXXXX nc nb ne +** model obtained from +** http://141.69.160.32/~krausg/Spice_Model_CD/Vendor%20List/Motorola/Spice/RFBJT/ +*.include MRF5711.lib +*XMRF5711 out in e MRF5711 +*Ie e 0 5m +*Ce e 0 1 + +** Example Tschebyschef Low Pass filter +C1 in 0 33.2p +L1 in 2 99.2n +C2 2 0 57.2p +L2 2 out 99.2n +C3 out 0 33.2p + +** Example RC +** see +** http://www.allenhollister.com/allen/files/scatteringparameters.pdf +*R2 in out 10 +*C1 out int5 30p +*R1 int5 0 10 + +*** End of circuit + + +** The following subcircuit to be changed only by an experienced user! + +*** Driver and readout +X1 in out S22 S12 S_PARAM + +.SUBCKT S_PARAM 22 66 5 7 +* Resistors emulate switches with Ron=0.001 and Roff=1e12 +* to switch driver to input and readout to output (and vice versa, see below) +RS1 22 2 0.001 +RS2 66 6 0.001 +RS3 22 6 1e12 +RS4 66 2 1e12 +*Driver +Vacdc 1 0 DC 'Vbias_in' AC 1 $ ac voltage and dc bias at input (applied through load resistor) +R1 1 2 'Rbase' +E1 3 0 2 0 2 $ amplify in port ac voltage by 2 +Vac 3 4 DC 0 AC 1 $ subtract driving ac voltage +R_loop 4 5 0.001 +R3 5 0 1 $ ground return for measure node 5 +*Readout +E2 7 0 6 0 2 $ amplify out port ac voltage by 2 +R4 6 8 'Rbase' $ load resistor at output (ac) +Vdc 8 0 DC 'Vbias_out' AC 0 $ dc bias at output (applied through load resistor) +.ends + +** Check the two ac lines below for being equal! +.control +set noaskquit +set filetype=ascii +*** measurement for s11 and s21 +op +** save bias voltages to vector +let Vdcnew=V(X1.1) $ former Vacdc +let Vacdcnew=v(X1.8) $ former Vdc +** first ac measurement (change this line only together with following ac line) +*ac lin 20 0.1G 2G $ use for bip transistor +ac lin 100 2.5MEG 250MEG $ use for Tschebyschef +*ac lin 101 1k 10G $ use for RC +** +** switch input and output +alter R.X1.RS1=1e12 +alter R.X1.RS2=1e12 +alter R.X1.RS3=0.001 +alter R.X1.RS4=0.001 +** switch bias voltages between in and out +alter V.X1.Vacdc DC=op1.Vacdcnew +alter V.X1.Vdc DC=op1.Vdcnew +*** measurement for s12 and s22 +op +** second ac measurement (change this line only together with ac line above) +*ac lin 20 0.1G 2G $ use for bip transistor +ac lin 100 2.5MEG 250MEG $ use for Tschebyschef +*ac lin 101 1 10G $ use for RC +** +let s11=ac1.s22 +let s21=ac1.s12 +settype s-param S11 S21 S22 S12 + +let S11db = db(s11) +let S12db = db(s12) +let S21db = db(s21) +let S22db = db(s22) +settype decibel S11db S21db S22db S12db + +let P11=180*ph(s11)/pi +let P21=180*ph(s21)/pi +let P22=180*ph(S22)/pi +let P12=180*ph(S12)/pi +settype phase P11 P21 P22 P12 + +let Rbase=@R.X1.R4[Resistance] +settype impedance Rbase + +*plot s11db s21db S22db S12db ylimit -50 0 xlog $ used with RC +plot s11db s21db S22db S12db ylimit -0.5 0 $ used with Tschebyschef +plot P11 P21 P22 P12 +plot smithgrid S11 S12 +*wrdata s3046 mag(S11) P11 mag(S21) P21 mag(S22) P22 mag(S12) P12 $ write simple table +wrs2p s3046.s2p $ write touchstone vers. 1 file s3046.s2p +.endc + +.end |