Programming and determining state of electrical fuse using field effect transistor having multiple conduction states
US7242239B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 2005 |
| Grant date | Jul 10, 2007 |
| Priority date | — |
| Expiry date | Jul 10, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C17/18
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A circuit is provided which is operable to program an electrically alterable element, e.g., fuse or antifuse, to a programmed state and determine whether the electrically alterable element is in the programmed state or not. Such circuit includes a multiple conduction state field effect transistor (“multi-state FET”) having at least one of a source or a drain coupled to the electrically alterable element to apply a current to the electrically alterable element. The multi-state FET has a first threshold voltage and a second threshold voltage, both being effective at the same time, the second threshold voltage being higher than the first threshold voltage. The gate is operable to control operation of the multi-state FET in multiple states including a) an essentially nonconductive state; b) a first or “low” conductive state when a gate-source voltage exceeds the first threshold voltage, in which the multi-state FET is biased to conduct a relatively low magnitude current for determining the state of the fuse; and c) a second conductive state when the gate-source voltage exceeds the second threshold voltage, in which the multi-state FET is biased to conduct a relatively high magnitude pr…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.