Integrated circuit option identification circuit and method
US4942358A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 2, 1988 |
| Grant date | Jul 17, 1990 |
| Priority date | — |
| Expiry date | Nov 2, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An identification circuit for use in identifying at least two integrated circuits having the same logic function but different input/output characteristics, each circuit having first and second isolated power supply conductors. A unilateral current conducting circuit having an input and an output is coupled between the first and second power supply conductors via conductive jumpers in all but one of the identifiable integrated circuits. The conductive jumpers are removed for one integrated circuit family. The other integrated circuit families have unique combinations of a resistor and at least one serially coupled diode wherein a predetermined potential is required to induce current to flow therethrough for each family. The potential of the first power supply conductor is increased in predetermined steps until current flow is detected, or a predetermined maximum potential is reached. The combination of the presence or absence of current flow and the potential at the first power supply conductor associated therewith provide the identification of the integrated circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.