Bidirectional interface circuit having a unipolar port and a bipolar port for logic signals
US4797582A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 13, 1987 |
| Grant date | Jan 10, 1989 |
| Priority date | — |
| Expiry date | May 13, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L5/1423
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
The invention relates to the transmission of logic signals. The circuit comprises a port D connected to a line for the transmission of unipolar logic signals and a port (D+, D-) connected to a pair of wires for the transmission of differential logic signals. Current generators (T4, T5) send a positive differential signal when a unipolar "low" logic signal is applied to port D. When the differential signal received at (D+, D-) must be transmitted on the D port by a "low" level, the signal representing the low level remains higher than the voltage level V.sub.L1 below which the voltage generators are activated, in order to prevent any blockage of the circuit by looping of the signals within the circuit. Application to the multiplexing of the flow of data processed in an automobile vehicle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.