Transformer data coupler with high common mode immunity
US7424060B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 19, 2004 |
| Grant date | Sep 9, 2008 |
| Priority date | — |
| Expiry date | Jan 4, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B3/02
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A data coupler comprises two CMOS drivers which are supplied with a data signal and a delayed version of the data signal to drive a primary winding of a transformer with narrow pulses of opposite polarity corresponding to respective edges of the data signal. A secondary winding of the transformer is coupled via a low pass filter to a data receiver, with a ground path for ac from one end of the secondary winding. The drivers are scaled with a ratio (N−1):(N+1), where the transformer has a primary-to-secondary turns ratio of N:1 and N is greater than one, to equalize voltage drops in the drivers due to consequent unequal common mode currents in the drivers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.