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:
Apr. 08, 1986
Filed:
Oct. 04, 1983
Richard G Beale, Freehold, NJ (US);
Apparajan Ganesan, Indianapolis, IN (US);
AT&T Technologies, Murray Hill, NJ (US);
AT&T Bell Laboratories, Murray Hill, NJ (US);
Abstract
A Schmitt trigger circuit 10 includes a pair of transmission gates 20, 22 connected, respectively, between a pair of threshold voltages V.sub.tH, V.sub.tL and the threshold input port 16 of a comparator 12. The control lead of one transmission gate 20 is connected to the output 18 of the comparator 12 through an inverter 24. The control lead of the other transmission gate 22 is connected directly to the output 18 of the comparator 12. The other input port 14 of the comparator 12 receives the signal input. Also disclosed is a circuit 26 for generating the reference voltages V.sub.tH, V.sub.tL. The circuit 26 includes an operational amplifier 28 driving a complementary pair of current mirrors (M1, M3, M5; M4, M6) which force current through a pair of resistors (R.sub.H, R.sub.L) to ground potential. The resistors (R.sub.H, R.sub.L) provide stable reference potentials.