Current-mode bidirectional input/output buffer
US6075384A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 1998 |
| Grant date | Jun 13, 2000 |
| Priority date | — |
| Expiry date | Mar 27, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K19/018592
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A bidirectional input/output buffer operates in a current mode to increase the data transfer rate between devices connected by a bidirectional transmission line. The buffer includes an output current source for generating an output current responsive to a data output signal. The output current is combined with an output current indicative of a data input signal received from another device over a transmission line, thereby forming a mixed current signal. The data input signal is restored from the mixed signal by a restoring circuit that compares the mixed signal to a reference current that depends on the value of the data output signal. The restoring circuit includes a current mirror and a reference current source that generates a reference current in response to the data output signal. To provide additional performance, an embodiment of a bidirectional input/output buffer utilizes a switchless structure having two comparators that compare the mixed signal to two different reference signals, thereby generating two comparison signals. A selector circuit selects one of the two comparison signals as the restored data input signal responsive to the data output signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.