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:
May. 07, 2019
Filed:
Jun. 04, 2018
Applicant:
Texas Instruments Incorporated, Dallas, TX (US);
Inventors:
Shailendra Kumar Baranwal, Murphy, TX (US);
Anant Shankar Kamath, Plano, TX (US);
Assignee:
TEXAS INSTRUMENTS INCORPORATED, Dallas, TX (US);
Primary Examiner:
Int. Cl.
CPC ...
G05F 3/26 (2006.01); H03K 19/003 (2006.01); H03K 19/0185 (2006.01); H03F 3/16 (2006.01);
U.S. Cl.
CPC ...
G05F 3/267 (2013.01); H03F 3/16 (2013.01); H03K 19/00315 (2013.01); H03K 19/018514 (2013.01); H03K 19/018585 (2013.01); H03F 2200/396 (2013.01);
Abstract
A bandgap voltage reference is provided in quasi-parallel with a resistor in the input path of a digital input circuit. Because of the quasi-parallel nature, the current used by the digital input circuit is limited to an amount based on the value of the external resistor. The input current is split between circuitry used to provide the logic signal across the selected isolation barrier and a sink transistor so that the current remains constant. This allows the digital input circuit to accurately limit input current without needing field-side power.