Broad band microwave biasing networks suitable for being provided in monolithic integrated circuit form
AssigneeMotorola, Inc.
InventorsRonald D. Fuller, Richard M. Dougherty, Craig L. Fullerton, Hugh R. Malone
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Abstract
Inductorless bias networks include a bias circuit having a bias return path which is coupled to and biases a variable impedance device in a relatively nonconductive state. Another bias circuit including a FET renders the variable impedance device relatively conductive in response to control signals so that one port is coupled to another port, for instance.
Claims32
A circuit for providing an impedance of a controlled magnitude between an input terminal and an output terminal, including in combination:
- a first diode responsive to changes in bias signals to provide impedances of different magnitudes, said first diode having first and second electrodes coupled between the input terminal and the output terminal;
- first bias means coupled to said first diode for selectively biasing said first diode in a relatively nonconductive state so that the input terminal is thereby isolated from the output terminal;
- means for providing control signals;
- and
- second bias means including a field effect transistor having first electrode, second electrode and control electrode, said control electrode being coupled to said means for providing control signals to selectively render said field effect transistor conductive, said first electrode being coupled to said first diode for providing bias signals for selectively rendering said first diode relatively conductive in response to said controls signals so that the input terminal is selectively coupled to the output terminal in response to said control signals.
A switching circuit for selectively connecting signals between a first terminal and a second terminal, said switching circuit including in combination:
- a first diode having first and second electrodes, said first electrode being coupled to the first terminal and said second electrode being coupled to the second terminal;
- a second diode having a first electrode and a second electrode, said second electrode of said second diode being coupled to the first terminal;
- first power supply conductor means;
- first bias means coupled between said first power supply conductor means and said first electrode of said second diode for rendering said second diode nonconductive;
- and
- second bias means including a first field effect transistor adapted to selectively provide forward biasing drive signals to said first electrode of said second diode to render said second diode conductive, said second diode thereby rendering said first diode conductive so that the signals applied to the first terminal are coupled to the second terminal through said first diode.
A variable attenuator circuit for providing a resistance of a controlled magnitude between an input terminal and an output terminal, including in combination:
- variable resistance means responsive to changes in bias signals to provide resistances of different magnitudes, said variable resistance means having first and second terminals coupled between the input terminal and the output terminal;
- means for providing control signals;
- and
- bias means including a field effect transistor having first electrode, second electrode and a plurality of control electrodes, said control electrodes being coupled to said means for providing control signals to selectively render said field effect transistor conductive, said field effect transistor thereby being responsive to said control signals to provide bias signals of different magnitudes, said first electrode being coupled to said variable resistance means for providing said bias signals thereto for selectively rendering said variable resistance means conductive in response to said controls signals so that the input terminal is selectively coupled to the output terminal in response to said control signals.
A circuit for providing an impedance of a controlled magnitude between an input terminal and an output terminal, including in combination:
- a first diode responsive to changes in bias signals to provide impedances of different magnitudes, said first diode having first and second electrodes coupled between the input terminal and the output terminal;
- means for providing control signals;
- and
- bias means including a field effect transistor having first electrode, second electrode and control electrode, said control electrode being coupled to said means for providing control signals to selectively render said field effect transistor conductive, said first electrode being coupled to said first diode for providing bias signals for selectively rendering said first diode relatively conductive in response to said controls signals so that the input terminal is selectively coupled to the output terminal in response to said control signals.
A variable attenuator circuit for providing a resistance of a controlled magnitude between an input terminal and an output terminal, including in combination:
- a first diode responsive to changes in bias signals to provide resistances of different magnitudes, said first diode having first and second terminals coupled between the input terminal and the output terminal;
- first bias means coupled to said first diode for isolated selectively biasing said first diode in a relatively nonconductive state so that the input terminal is thereby isolated from the output terminal;
- means for providing control signals;
- and
- second bias means including a field effect transistor having first electrode, second electrode and control electrode, said control electrode being coupled to said means for providing control signals to selectively render said field effect transistor conductive, said first electrode being coupled to said first diode for providing bias signals thereto for selectively rendering said first diode relatively conductive in response to said control signals so that the input terminal is selectively coupled to the output terminal in response to said control signals.
Dependencies are inferred from the claim text.