Interface circuit
US4894864A · kind A · utility
13Cited by
4References
5Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jul 14, 1987 |
| Grant date | Jan 16, 1990 |
| Priority date | — |
| Expiry date | Jul 14, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M3/005
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An analog/digital interface circuit in which an analog terminating impedance is partially synthesized by supplying a digital output (T) signal to a digital input (R) via a digital filter (17). A variable resistive transmission path is connected across the analog ports the resistance of which may be varied along with characteristics of the digital filter in order to simulate any required terminating impedance. The structure facilitates changing Z.sub.T while maintaining the required frequency response and remaining stable.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.