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. 07, 1988
Filed:
Jun. 15, 1987
Jeffrey D Ganger, Austin, TX (US);
Jeff D Stump, Elgin, TX (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
An input protection circuit is provided which prevents positive and negative voltages significantly higher than a supply voltage potential from damaging operational circuitry connected to an input terminal. A bipolar transistor has current conducting electrodes connected between the supply voltage and the input terminal. A first MOS transistor is coupled to the bipolar transistor for selectively eliminating a forward biased junction between the base and collector of the bipolar transistor in response to the sign and magnitude of an input signal. A second MOS transistor is coupled to the bipolar transistor for selectively eliminating a forward biased junction between the base and emitter of the bipolar transistor in responses to the sign and magnitude of the input signal.