Semiconductor integrated circuit system having function of automatically adjusting output resistance value
US6049221A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 8, 1998 |
| Grant date | Apr 11, 2000 |
| Priority date | — |
| Expiry date | Jul 8, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K19/0005
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A semiconductor integrated circuit system having a function of automatically adjusting an output resistance value with reference to a temperature of an LSI which is operating. When a count value obtained from a counter by counting the output of a timer becomes equal to a predetermined value, a temperature sensor measures temperatures of LSIs. If a temperature fluctuation measured from a previous measured value is greater than a predetermined width, then a control apparatus issues an output resistance value adjustment request signal to output resistance adjustment units of the LSIs. When receiving the output resistance value adjustment request signal, the output resistance value adjustment units stop the signal transmission between the LSIs, adjust output resistance values of output circuits in such a manner that the output resistance values are matched with a characteristic impedance of a transmission line, and maintains the adjusted output resistance values until the output resistance value adjustment units receive next output resistance value adjustment request signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.