US Patent 7859991 Signal transmitting apparatus, power supplying system, and serial communication apparatus

A signal transmitting apparatus includes a sending part and a receiving part. The sending part converts each width of a plurality of digital input signals into a voltage in accordance with a predetermined weight, generates a send signal by adding voltages converted from the plurality of digital input signals, and outputs the send signal. The receiving part receives the send signal from the sending part, compares the send signal with a plurality of predetermined voltages, generates each of the digital input signals, and outputs each of the digital input signals.