A 0.15-mm-thick noncontact connector for mipi using a vertical directional coupler

A noncontact and housing-less thin-thick connecting method was developed for mobile industry processor interface (MIPI) applications. This paper describes the world's first 0.15-mm-thick connector using a vertical directional coupler (VDC) which enables simultaneous two-link communication with one coupler without fatal performance degradation. We have analyzed the conditions for isolating two links in a coupler, and the design method is discussed. A fully balanced pulse transmitter implemented in 90-nm CMOS technology significantly suppressed electromagnetic interference (EMI), which agrees well with MIPI requirements. An experimental liquid crystal display interface system reached a maximum data rate of 2.3 Gb/s/link at a bit error rate of less than 10^-12 and a power consumption of 1.47~pJ/b. The timing margin of single link was 320 ps (=64% U.I.) and of two links was 305 ps (= 61% U.I.) at 2.0 Gb/s.