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measurement of chip inductors

Question asked by nsm on Jul 6, 2012
Latest reply on Jul 6, 2012 by Dr_joel

I am trying to measure quality factor,ESR and the inductance vales of chip inductors using a PNA in the 100Mhz to 6Ghz range. We have made a simple test fixture that has a SMA(m) connector and the other end of the connector connected to a PCB with a centre conductor and ground plane(See pic attached). 

We do a one port cal over the frequency band. Then we do auto port extension by connecting the fixture and leaving it open.

Then we place the inductor between the centre conductor and the ground plane and read the values on the smith chart for the ESR(the real part) and the inductance value by placing markers at the frequencies desired. The q factor is calculated as the real part/imaginary part.

Is this an accurate method for measuring the inductors?Can we see the SRF(self resonant frequency) by looking at the frequency point where on the smith chart, the inductive impedance turns capacitive?