Patent ID: 7560969

Claim:
A receiver of a high speed digital interface, comprising: at least one differential amplifier for receiving a small differential signal at a pair of input terminals and outputting an amplified differential signal; a pair of resistive elements, each of the resistive elements having one end coupled to one of the input terminals of the differential amplifier and the other end receiving a reference voltage; a pair of low-pass filters for receiving the amplified differential signal and deriving a differential feedback signal from the amplified differential signal; a first transistor and a second transistor having drains respectively coupled to the input terminals of the differential amplifier and gates receiving the differential feedback signal; a third transistor having a drain coupled to sources of the first transistor and the second transistor, a source receiving a ground voltage and a gate receiving a bias voltage; a fourth transistor having a source receiving an operational voltage, a drain outputting the reference voltage and a gate coupled to the drain of the fourth transistor; a fifth transistor having a source receiving the operational voltage and a drain coupled to the gate of the fourth transistor; a sixth transistor having a source receiving the operational voltage and a gate coupled to a gate of the fifth transistor and a drain of the sixth transistor; a seventh transistor having a drain coupled to the drain of the fifth transistor and a gate receiving a common mode voltage; a eighth transistor having a drain coupled to the drain of the sixth transistor and a gate receiving the reference voltage; and a ninth transistor having a drain coupled to sources of the seventh transistor and the eighth transistor, a source receiving the ground voltage and a gate receiving the bias voltage.