Differential amplifier with de-emphasis
US8536944B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 15, 2012 |
| Grant date | Sep 17, 2013 |
| Priority date | — |
| Expiry date | May 2, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L25/0272
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A programmable current driver provides de-emphasis capability. A number of identical transmitter slices, consisting of a unit current source and a unit differential pair, are connected in parallel to the termination resistors. As the transmitter slices are identical, the current density through the differential pairs are identical, and the VDS voltages across them (as well as the VDS voltages across the unit current sources) are the same, ensuring that the current through each slice is identical (within the limits of device matching). Biasing circuitry ensures that each unit current source sinks a current having a fixed proportion to the total current.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.