1 Gb/s, 50 .MU.m * 50 .MU.m Pads on Board Wireless Connector Based on Track-and-Charge Scheme Allowing Contacted Signaling

Abstract

A capacitive coupling wireless connector circuit is implemented with 50 μm × 50 μm pads, which is a 25X reduction of pad size compared with previous wireless connectors by allowing contacting and non-contacting modes. The proposed track and charge scheme allows both contacting and non-contacting communication through PCB capacitive pads. By making the precharge level of the input V DD or V SS , instead of 1/2 V DD , the time necessary to precharge is reduced. The proposed digitally tunable comparator does not require analog voltages, reduces the power to less than 1/20 at lower frequencies compared to previous capacitive coupling receivers. A test chip successfully transmitted and received 1 Gb/s, 2 7 − 1PRBS signal at 1 mW while increasing design freedom of the wireless connectors.