Very low-voltage swing while high-bandwidth data transmission through 4096 bit TSVs

A three tier, three dimensional chip stack forms wide I/O test vehicle and demonstrates 100 GByte/sec in vertical data channels with 4096 bit TSVs. The operation is stable for the wide range of supply voltage from 0.75 V to 1.2 V. An in-place waveform capture and a built-in self test mechanism embody on-chip diagnosis of high-bandwidth data transmissions, by monitoring signal waveforms as well as measuring eye openings and bit error rates.