Abstract:
In Radio Frequency Integrated Circuits (RFIC) or high frequency digital
ICs, there is a demand to probe the internal nodes for testing. The ultra low
capacitance RFIC probe presented in his work is a flexible tool for these
applications. The probe utilizes the coupling between a tungsten needle and the
inner conductor of a coaxial cable, forming a capacitor. The ultra low capacitance
of the probe enables low probe loading on the circuit under test. With capacitive
coupling, the probe output is the derivative of the input signal.
Through the use of probe calibration and Fourier transforms, the probed
signal can be recovered. Probe calibration develops a transfer function enabling
recovery of time domain signals. By utilizing a simple mechanical design, input
impedance is maximized and parasitic components are minimized.
