Data card circuits
US4841133A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 30, 1988 |
| Grant date | Jun 20, 1989 |
| Priority date | — |
| Expiry date | Mar 30, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2221/2105
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An integrated circuit for a data or "smart" card includes a non-volatile memory (8) having a transport code preprogrammed therein, control circuitry (10), a comparator (24) for comprising an externally-applied code and the transport code, and a fuse (26) which is blown if the two codes match thereby allowing the card to be initialised with a personal identification number and initial credit values. A second fuse (28) may also be provided which is blown if the two codes do not match and sensing means (32, 34) sense the status of the two fuses (26, 28) and block any further attempts to initialise the card if the second fuse (28) is blown and the first fuse (26) is not.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.