Patent ID: 8929431
Filing Date: 2015-01-06
Classification: H04L

Abstract:
1. A transceiver incorporated in a data communication system, coupled to a communication path of the system, whereby bits are serially transmitted over the communication path during respective bit intervals as a communication path signal comprising PWM (pulse width modulation) encoded signals respectively expressing a dominant code and a recessive code, each of the dominant code and recessive code comprising a transition from a recessive level to a dominant level at a bit boundary and a subsequent return to the recessive level within a bit interval after a specific corresponding duration has elapsed, the corresponding duration being longer for the dominant code than for the recessive code, the transceiver configured to transmit the dominant code by overwriting, with the dominant level, a part of a recessive-level portion of a recessive code that flows on the communication path; the transceiver including receiver circuitry configured for receiving the communication path signal, encoding circuitry configured to generate a transmission signal and to respond to a request for transmitting data expressing a dominant code by changing the transmission signal from an inactive level to an active level at the timing of a boundary edge and subsequently returning the transmission signal to the inactive level after the corresponding duration of the dominant code has elapsed, the boundary edge comprising a transition of the communication path signal from the inactive level to the active level, waveform shaping circuitry configured for shaping respective edges of a waveform of the transmission signal with an edge slope, to obtain a shaped signal varying between the active level and the inactive level, and drive circuitry configured to hold the communication path signal at the dominant level while the shaped signal is at the active level thereof; wherein the waveform shaping circuitry is configured to form the edge slope of the shaped signal to have a first degree of steepness at a transition from the inactive level to the active level and a second degree of steepness, less than the first degree, at a transition from the active level to the inactive level.