Microminiature integrated circuit impedance device including weighted elements and contactless switching means for fixing the impedance at a preselected value

A microminiature terminal-adjustable integrated circuit impedance device comprising:

• an electrically insulating substrate;
• a first input terminal and an output terminal formed on said substrate;
• a plurality of electrically permanently alterable contactless voltage-responsive circuit elements formed on said substrate, each said voltage-responsive circuit element normally having a first electrical characteristic and having a second electrical characteristic different from said first electrical characteristic following the application thereacross of a predetermined voltage;
• a plurality of impedance elements formed on said substrate each having one side connected to said input terminal and another side connected to said output terminal by a corresponding one of said voltage-responsive circuit elements to form a first combination of impedance elements having an impedance of a first predetermined value;
• a plurality of adjustment terminals formed on said substrate each being respectively connected to one side of a corresponding one of said impedance elements such that when said predetermined voltage is applied between one of said voltage adjustment terminals and said output terminal, the voltage-responsive circuit element connected therebetween is caused to assume said second electrical characteristic thereby either effectively eliminating, or if initially eliminated, including the corresponding impedance element from said first combination to form a second combination of said impedance elements between said input terminal and said output terminal having a second predetermined impedance value.

A microminiature terminal-adjustable integrated circuit impedance device comprising:

• a substrate;
• a first plurality of impedance elements formed on said substrate with each element having an impedance;
• a first input terminal;
• an output terminal;
• a first plurality of electrically permanently alterable contactless switching means formed on said substrate, each of said switching means being associated with one of said plurality of impedance elements and having initially a first switching state and being permanently alterable by application of electrical energy to an opposite switching state;
• a first interconnecting means interconnecting said impedance elements and said switching means in a first circuit configuration between said first input terminal and said output terminal such that the impedance between said first input terminal and said output terminal is of a first value;
• and
• a plurality of adjustment terminals each being connected to a different one of said plurality of switching means for facilitating the application of electrical energy thereto to cause such switching means to change to said opposite switching state, whereby the application of electrical energy to selected ones of said adjustment terminals causes a second circuit configuration having a preselected second impedance value to be formed between said first input terminal and said output terminal.