Low-voltage differential driver with opened eye pattern
US6590432B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 2002 |
| Grant date | Jul 8, 2003 |
| Priority date | — |
| Expiry date | Sep 26, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L25/0272
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A differential output buffer has a primary stage and a secondary stage that each directly drive differential outputs. Link transistors between the secondary stage and the differential outputs are eliminated. The primary stage continuously receives differential inputs applied to gates of n-channel sourcing and sinking transistors. The sources of the sourcing transistors and the drains of the sinking transistors are connected to the true and complement differential outputs. The secondary stage also has n-channel sourcing and sinking transistors directly connected to the differential outputs. Pulsed inputs applied to secondary-stage gates are normally low, disabling the sourcing and sinking transistors in the secondary stage to disable the secondary stage. However, during a switching transient, the pulsed inputs are pulsed on, allowing the secondary stage to drive a boost current to the differential outputs. This boost current sharpens rise and fall edges to compensate parasitic capacitances, opening the eye pattern.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.