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:
Jul. 06, 1982
Filed:
Jan. 07, 1980
Joseph J Connolly, Jr, San Jose, CA (US);
James B Cecil, Santa Clara, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
A multi-stage resistive ladder network which uses extra stages to trim out resistance discrepencies. All of the stages are interconnected in a series. Nominally, current is divided in half within each stage. Half of the current is gated onto a bus in response to logic control signals, and the other half of the current is passed onto the next succeeding stage. Due to various processing limitations, the resistors comprising each stage vary slightly from their nominal value, which in turn upsets the current division. To compensate for this additional current dividing stages are serially connected to the last stage of the ladder. Current from these additional stages are selectively coupled onto the bus in response to the logic signals in addition to the current which is normally coupled thereto.