Low Pass Distributed RC Filter using an MOS Transistor with Near Zero Phase Shift at High Frequencies.

An MOS transistor with zero drain to source voltage is analysed as a filter element. Using a four terminal analysis, it is shown that the transistor can act as a distributed low pass filter with phase shift recovery at high frequencies. Numerical simulations of the filter gain and phase characteristics including the transistor parasitics are also presented. This filter has been used successfully in the design of self biasing high gain Gigahertz band amplifiers.