Patent ID: 8183893

Claim:
A driver comparator circuit configured to provide bidirectional signal transmission with a communication target device via a transmission line, the driver comparator circuit comprising: an input/output terminal connected to the transmission line; a first resistor arranged such that a first voltage is applied to a first terminal thereof, and a second terminal thereof is connected to the input/output terminal; a second resistor arranged such that the first voltage is applied to a first terminal thereof; a tail current source configured to generate a predetermined tail current; a current switch configured to receive data to be transmitted to the communication target device, to select one terminal from among the second terminal of the first resistor and a second terminal of the second resistor according to the value of the data thus received, and to connect the second terminal thus selected to the tail current source; a voltage dividing circuit including a third resistor and a fourth resistor provided in series between the second terminal of the first resistor and the second terminal of the second resistor; a load balancer including a fifth resistor arranged such that a second voltage is applied to a first terminal thereof, and a second terminal thereof is connected to the second terminal of the second resistor; and a comparator configured to compare the electric potential at a connection node that connects the third and fourth resistors with a predetermined first threshold voltage.