ZXtalk-B IP portfolio

     The patent families P40, P42 and P47 are mainly intended to be applied to the ZXtalk techniques for the reduction of internal crosstalk and echo in electrical interconnections such as the one used in a system in package (SiP), a multi-chip module (MCM) or a printed circuit board (PCB). The ZXtalk method improves the performance of links used to obtain m transmission channels using an interconnection having m transmission conductors. The link features a low crosstalk between the transmission channels, in spite of a narrow spacing between the transmission conductors. The link also uses fewer conductors than m differential links.

     A short presentation of the ZXtalk method is available in the Section 3 of this page. Several peer-reviewed technical articles published on this subject may be downloaded here. Excem also offers two Seminars and a free electronic book presenting the technical background for assessing and implementing this technology.

     The patent family P47 is necessary for expanding the applicability of the ZXtalk methods to an interconnection which cannot be modeled as a uniform multiconductor transmission line, for instance an interconnection extending from a first chip to a second chip. A topical subject is the application of the ZXtalk method to top-side chip-to-chip bridges. Top-side chip-to-chip bridges are for instance described in a paper entitled "A 47 x 10Gb/s 1.4mW/gb/s parallel interface in 45nm CMOS", published in the IEEE Journal of Solid-State Circuits, vol. 45, No. 12, Dec. 2010. The Authors of this paper are with Intel. Three recent patents assigned to Intel apply the concept of modal signaling to parallel interfaces used in top-side chip-to-chip bridges: US patent 7,816,779, US patent 7,989,946 and US patent 8,450,201. In our view, the patent family P47 is needed for such applications. It might also be needed to implement the invention of Rambus disclosed in US patent 8,279,676.

     The patent families P40 and P42 can also be used in links where the ZXtalk and ZXnoise methods are combined to obtain a reduction of internal and external crosstalk.

     The balanced current-sensing differential amplifier disclosed in the P49 patent family may be used as the input circuit of a line receiver for a differential or pseudo-differential link.

     The patent family P42 (US 8,125,240) was referenced by USPTO examiners during the prosecution of US 8,903,009 (assigned to Broadcom Corporation).

     The ZXtalk-B portfolio is presented in this slide show. For a conference with technical experts, please contact us. We can also provide several reports relating to these inventions.