Integrated distributed RC low-pass filters

Abstract

A low pass filter including a number of different filter sections each having two input and two output terminals as well as a common terminal. Each filter section includes first and second resistors connected in series between respective first and second input terminals and first and second output terminals. Each of the resistors is formed by depositing a pattern of resistive material over a conducting plate with an intervening dielectric layer to provide a distributed capacitance between the resistive pattern and the conductive plate. Resistive elements are connected between at least one combination of (1) each of the conducting plates to the common terminal and (2) the conducting plates. A resistor is connected between the output terminals of at least one of the filter sections. The filter sections are cascade connected such that the output terminals in one section are connected to the input terminals of the next. Additionally, a step-wise adjustable notch frequency filter is disclosed to include at least one input and one output terminal and a ground terminal. A number of resistive elements are constructed as thin films and deposited over a corresponding number of conducting plates with an intervening dielectric layer. A number of switches are arranged to selectively bypass certain of the resistive elements and a corresponding number of switches are arranged to be able to selectively connect together certain of the connecting plates associated with the unbypassed resistor elements to a common terminal which is connected through resists to the ground terminal.

Dependencies are inferred from the claim text.