Measure and Verify FT85-52 X2 10T Balun CMR

Using measured CMR and measured Complex Permeability
Fair-Rite 5952020601


10T Impedance Measurement



10T Two Port VNWA Impedance Measurement
  • Calibration process
    Delays = Cal Kit Delay + -106ps (11mm Amphenol 031-203-RFX)
  • S11 from t2s(S21) with S21 12-term Correction
  • Marker 2, 1.49MHz, |Z| = 250.42Ω
    "Understanding, Building, and Using Baluns and Ununs" By Jerry Sevick,
    Page 3, "Inductive reactance a least 10 times greater than RL/2."



Compute Complex Permeability

  • Use 10T Impedance Measurement exported s1p file
  • Lo = 0.0004606 * Log10(OD / ID) * Ht * Turns2 (mm)
  • 10T Lo = 0.0004606 * Log10(21.73 / 13.64) * 12.71 * 102 = 0.1184uH
  • μi = 229.4 (at 100kHz)
  • Write Complex Permeability file, FT85-52-x2-CP.dat, using: 
    //Plots
legend "FT85-52-x2-CP.dat", "Generic 1 1e6 2 3";
write ",%12g,%12g", D1.up, D1.upp;
  • Files: BalunMeasure.zip

ss-FT85-52-x2-10T-CP.ssx



Compare Measured Complex Permeability to Fair-Rite 52

ss-FT85-52-x2-CPvsFR.ssx



Measure Ten Turn Common Mode Rejection (CMR)

OSLTTmatch Female Arbitrary Calibration using SDR-Kit BNC Calibration Kit


CMR Fixture Schematic


VNWA CMR Fixture Measurement



SimSmith Balun Model

  • Validate Measured CMR matches Balun model CMR
  • Use FT85-52-x2-CP.dat measured Complex Permeability file
  • SimSmith Trace:
    • ModelCMR = SimSmith Balun Model CMR
    • TwoPortCMR = VNWA measured CMR
    • t2sS21 = R1 = Two Port CMR t2s(S21)
  • Files: BalunMeasure.zip

ss-FT85-52-x2-10T-CMR.ssx


Balun Model RUSE A





Measure and Verify FT114A-31 10T Balun CMR

Using measured CMR and measured Complex Permeability
Fair-Rite 2631801202


10T Impedance Measurement



10T Two Port VNWA Impedance Measurement
  • Calibration process
    Delays = Cal Kit Delay + -106ps (11mm Amphenol 031-203-RFX)
  • SRF ~= 17.3MHz
  • S11 from t2s(S21) with S21 12-term Correction



2T Impedance Measurement


2T Two Port VNWA Impedance Measurement
  • Calibration process
    Delays = Cal Kit Delay + -106ps (11mm Amphenol 031-203-RFX)
  • S11 from t2s(S21) with S21 12-term Correction



Compute Complex Permeability

  • Use both 10T and 2T Impedance Measurement exported s1p files
  • Lo = 0.0004606 * Log10(OD / ID) * Ht * Turns2 (mm)
  • 10T Lo = 0.0004606 * Log10(29.04 / 19.02) * 13.81 * 102 = 0.1169uH
  • μi = 1178 (at 100kHz)
  • 2T Lo = Adjusted to Match 10T 100kHz μ' measurement
  • 10T Complex Permeability computation invalid above about 3MHz
  • Write Complex Permeability file, FT114A-31-CP.dat, using: 
    //Plots
legend "FT114A-31-CP.dat", "Generic 1 1e6 2 3";
if(G.MHz < 1) {
    write ",%12g,%12g", D1.up, D1.upp;
} else {
    write ",%12g,%12g", D2.up, D2.upp;
}
  • Files: BalunMeasure.zip

ss-FT114A-31-2T-10T-CP.ssx



Compare Measured Complex Permeability to Fair-Rite 31

ss-FT114A-31-CPvsFR.ssx



Measure Ten Turn Common Mode Rejection (CMR)

OSLT Female Arbitrary Calibration using SDR-Kit BNC Calibration Kit


CMR Fixture Schematic


VNWA CMR Fixture Measurement



SimSmith Balun Model

  • Validate Measured CMR matches Balun model CMR
  • Use FT114A-31-CP.dat measured Complex Permeability file
  • Trace ModelCMR = SimSmith Balun Model CMR
  • Trace TwoPortCMR = VNWA measured CMR
  • Files: BalunMeasure.zip

ss-FT114A-31-10T-CMR.ssx


Balun Model RUSE A





Measure and Verify FT240-43 10T Balun CMR

Using measured CMR and measured Complex Permeability
Old core from Amidon Inc.


10T Impedance Measurement



10T Two Port VNWA Impedance Measurement
  • Calibration process
    Delays = Cal Kit Delay + -106ps (11mm Amphenol 031-203-RFX)
  • S11 from t2s(S21) with S21 12-term Correction



3T Impedance Measurement


3T Two Port VNWA Impedance Measurement
  • Calibration process
    Delays = Cal Kit Delay + -106ps (11mm Amphenol 031-203-RFX)
  • S11 from t2s(S21) with S21 12-term Correction



Compute Complex Permeability

  • Use both 10T and 3T Impedance Measurement exported s1p files
  • Lo = 0.0004606 * Log10(OD / ID) * Ht * Turns2 (mm)
  • 10T Lo = 0.0004606 * Log10(60.86 / 35.41) * 12.7 * 102 = 0.1376uH
  • μi = 852.4 (at 100kHz)
  • 3T Lo = Adjusted to Match 10T 100kHz μ' measurement
  • 3T Complex Permeability computation invalid below about 1MHz
  • 10T Complex Permeability computation invalid above about 10MHz
  • Write Complex Permeability file, CP.dat, using: 
    //Plots
legend "CP.dat", "Generic 1 1e6 2 3";
if(G.MHz < 2) {
    write ",%12g,%12g", D1.up, D1.upp;
} else {
    write ",%12g,%12g", D2.up, D2.upp;
}
  • Files: BalunMeasure.zip

ss-FT240-43-3T-10T-CP.ssx



Compare Measured Complex Permeability to Fair-Rite 43

ss-FT240-43-CPvsFR.ssx



Measure Ten Turn Common Mode Rejection (CMR)

OSLT Female Arbitrary Calibration using SDR-Kit BNC Calibration Kit


CMR Fixture Schematic


VNWA CMR Fixture Measurement



SimSmith Balun Model

  • Validate Measured CMR matches Balun model CMR
  • Use CP.dat measured Complex Permeability file
  • Trace ModelCMR = SimSmith Balun Model CMR
  • Trace TwoPortCMR = VNWA measured CMR
  • Files: BalunMeasure.zip

ss-FT240-43-10T-CMR.ssx


Balun Model RUSE A