Methods and systems for skew tolerance in and advanced detectors for vector signaling codes for chip-to-chip communication

An apparatus comprising:

• a plurality of codeword detection circuits configured to decode symbols of codewords of at least a ternary vector signaling code by generating a set of digital output signals,
• each codeword detection circuit comprising:
• a set of n weighted inputs comprising a set of input weighting factors, wherein n is an integer greater than 2;
• two summing nodes, each summing node configured to receive at least one of the n weighted inputs as summing-node inputs, each summing node configured to generate a respective summing-node value of a pair of summing-node values, each respective summing-node value representing a sum of the summing-node inputs;
• and,
• a differential comparator configured to produce a respective digital output of the set of digital outputs, the digital output indicating which summing-node value of the pair is larger;
• and,
• a detector configured to obtain the symbols of a codeword based on the set of digital output signals.

A circuit comprising:

• at least three transistor circuits configured to receive at least three inputs, respectively, each input associated with a symbol of a codeword of a vector signaling code, each transistor circuit configured to generate a corresponding weighted input of a set of at least three weighted inputs, each weighted input having a respective input weighting factor of a set of at least three distinct input weighting factors;
• two summing nodes, each summing node receiving one or more of the at least three weighted inputs as summing-node inputs, each summing node generating a respective summing-node value of a pair of summing-node values, each summing-node value representing a sum of the summing-node inputs;
• and
• a differential comparator accepting the pair of summing-node values as comparator inputs, the differential comparator configured to produce a digital output indicating which summing-node value of the pair of summing-node values is larger.