Patent ID: 8220947
Filing Date: 2012-07-17
Classification: G01R,H03F,H03G

Abstract:
1. A differential driver circuit configured to output a differential signal to a differential transmission line, the differential driver circuit comprising: a first output terminal connected to one side of the differential transmission line; a second output terminal connected to the other side of the differential transmission line; a first resistor arranged such that a predetermined voltage is received via one terminal thereof, and the other terminal thereof is connected to the first output terminal; a second resistor arranged such that a predetermined voltage is received via one terminal thereof, and the other terminal thereof is connected to the second output terminal; a plurality of differential pairs, each of which comprises a first transistor and a second transistor arranged such that the sources thereof are connected to each other, a drain of the first transistor is connected to the first output terminal and one side of a differential signal to be transmitted is input to a gate of the first transistor, and a drain of the second transistor is connected to the second output terminal and the other side of the differential signal to be transmitted is input to a gate of the second transistor; a plurality of first current sources severally arranged according to a plurality of respective differential pairs, and which are each configured to supply a tail current to the corresponding differential pair; and a plurality of pre-drivers severally arranged according to the plurality of respective differential pairs, and which are each configured to output gate signals to the gates of the first and second transistors of the corresponding differential pair, to independently switch between an enable state and a disable state, to output, in the enable state, the gate signals according to the differential signal, and to output, in the disable state, gate signals having levels which instruct the first and second transistors of the corresponding differential pair to switch off.