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:
Mar. 21, 1989
Filed:
May. 01, 1987
Carl J Scharrer, Plano, TX (US);
Roland H Pang, Plano, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A multiport random access memory cell includes a current mode latch (68) for storing two logic states and interface circuits for interfacing the input of the latch (68) with multiple input ports and the output of the latch (68) with multiple output ports. The interface circuitry comprises current switches (70-76) for switching current to a current source in the presence of a write select and a row select signal to override the holding current in the current mode latch. The output interface circuitry includes current sensors (78-84) for sensing the logic state in the latch and outputting it to the select output ports in the presence of a row select signal. The current switches and the current sensors utilize current mode logic and with a common current source. The current source is disable in the absence of any row select signal such that power is not drawn by the memory cell in the unselected state.