Low-noise, high-speed data transmission using a ringing-canceling output buffer

The proposed ringing-canceling output buffer transmits a superimposed two-step pulse that almost completely cancels the ringing in the received waveform. Simulation showed that this circuit increases the noise margin by a factor of 2.6 compared to using a conventional circuit in a bus interface at a data rate of 200 MHz. A test circuit was designed and fabricated to experimentally verify the fundamental ringing-canceling effect. Compared with other approaches to reducing ringing, the ringing-canceling output buffer provides a bigger improvement in the noise margin with a smaller signal-delay. This output buffer is promising for improving the data transfer rate of the memory bus.