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:
Dec. 05, 2000
Filed:
Dec. 15, 1998
Terence G Blake, Dallas, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
An output buffer with switching PMOS drivers (10) is disclosed. According to one embodiment, output buffer (10) includes a first output driver (62) and a second output driver (68). A first output cascode (64) coupled to the first output driver (62) protects the gate oxide of the first output driver (62) from voltage changes on the output (16). A second output cascade (66) coupled to the second output driver (68) protects the gate oxide of the second output driver (68) from voltage changes on the output (16). A level shifter (30) includes multiple cascode devices (46, 48, 50, 52) and switches the first output driver (62) according to the values of a data input (12) and an enable input (14). Switching circuitry (60) coupled to the second output cascode (64) allows the first output cascode (64) to protect the gate oxide of the first output driver (62) and provides extra drive for the output buffer (10).