Patent ID: 7514968

Claim:
Differential output driver circuitry comprising: a pull-up current source connected between a power supply voltage source and a first node; a pull-down current source connected between a second node and ground; first and second transistors connected in series between the first and second nodes; third and fourth transistors connected in series between the first and second nodes; a first output node connected between the first and second transistors; a second output node connected between the third and fourth transistors; first and second resistors connected in series between the first and second output nodes; and a common-mode voltage source connected between the first and second resistors, wherein the pull-up current source comprises: fifth and sixth transistors connected in series between the power supply voltage source and the first node; seventh and eighth transistors connected in series between the power supply voltage source and a first reference current source; a first connection that connects together a gate terminal of the seventh transistor, a source terminal of the eighth transistor, and a gate terminal of the fifth transistor; and a second connection that connects together a first bias voltage source, a gate terminal of the eighth transistor, and a gate terminal of the sixth transistor.