1 Gb/s, 50 μm × 50μm Pads on Board Wireless Connector Based on Track-and-Charge Scheme Allowing Contacted Signaling

摘要

A capacitive coupling wireless connector circuit is implemented with 50μm x 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 Vdd or Vss, instead of 1/2 Vdd, 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, 27 - 1PRBS signal at 1 mW while increasing design freedom of the wireless connectors.