The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 23, 1981
Filed:
Apr. 09, 1979
Harry J Boll, Berkeley Heights, NJ (US);
Richard M Goldstein, Summit, NJ (US);
Bell Telephone Laboratories, Incorporated, Murray Hill, NJ (US);
Abstract
An IGFET push-pull driver circuit includes an output stage having pull-up and pull-down IGFETs for driving an output node. An inverter stage drives the gate of the pull-up IGFET. A current sensing IGFET biased to represent a resistance is coupled between the pull-up IGFET and the output node to provide a voltage drop which is proportional to the current flowing through the pull-up IGFET. A regulating IGFET with its channel coupled between the gate of the pull-up IGFET and the output node and with its gate coupled to the juncture of the pull-up IGFET and the current sensing IGFET, responds to the voltage drop across the current sensing IGFET to provide feedback control of the conductance of the pull-up IGFET. The maximum output current of the driver is limited to a value which remains substantially constant over a wide range of processing parameters, operating temperature and load impedance.