Programmable sense amplifier for read only memory
US4821239A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 25, 1987 |
| Grant date | Apr 11, 1989 |
| Priority date | — |
| Expiry date | Aug 25, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C17/12
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A programmable sense amplifier in accordance with the present invention includes an input multiplexer which receives a plurality of data input signals from the column lines of a ROM and provides a selected one of a data input signals as a data output signal based on control signals proviced to the input multiplexer. The voltage level of the data output signal corresponds to the number of 1's contained in the selected column line. A sensing stage receives the data output signal and amplifies it. The amplified signal is then provided to an XOR gate which either does or does not invert the amplified signal, based upon the state of the select node to which one of the XOR gate inputs is connected. The state of the select node is determined by a programmable internal multiplexer. The internal multiplexer comprises a number of FET switching transistors corresponding to the number of data input signals. Each of the switching transistors has one of its electrode areas commonly-connected to the select node. The other area of each switching transistor is selectively, i.e. programmably, connected either to the negative supply V.sub.SS or the positive supply V.sub.CC depending upon whether or n…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.