ELECTRONIC DEVICE

摘要

PURPOSE: An electronic device is provided to specify a driver circuit structure and a characteristic impedance of a transmission line in an I/O circuit unifying a driver circuit with a bus wiring system including the transmission line and a termination circuit matched with the transmission line so that it can enhance the transmission speed of the bus wiring system. CONSTITUTION: An electronic device comprises a transmission line(1), a termination resistance(2) and a differential driver(3). The transmission line(1) transmits a differential compensation digital signals. The termination resistance(2) composes a bus wiring system by matching the transmission line(1). The current switch type differential driver(3) composes the I/O circuit by associating with the bus wiring system. The differential driver(3) includes a pMOS transistor(Q1), an nMOS transistor(Q2), an nMOS transistor(Q3), a pMOS transistor(Q4), a resistance(R1) for a power source and a resistance(R2) for an electrical earth. The digital compensation signals are extracted from the connection nodes between the transistors(Q1,Q2), and between the other transistors(Q3,Q4), and transmitted to the transmission line(1). The differential driver can be composed by a bipolar circuit structure.