Patent ID: 7719361

Claim:
A single stage differential amplifier comprising a first electrical path formed directly between an output node of a single first transistor and a first load impedance, a second electrical path formed directly between an output node of a single second transistor and a second load impedance, third and fourth electrical paths coupled, respectively, to first and second biasing nodes of the single first and second transistors for providing a differential voltage input signal between the first and second biasing nodes, a tail-current transistor coupled to the first and second transistors for providing a current through each of the first and second electrical paths, a differential voltage output signal provided directly between the first and second electrical paths and provided directly between the output nodes of the single first and second transistors, the differential voltage output signal providing amplification for the single stage differential amplifier, an input end of a feedback amplifier coupled directly to the first and second electrical paths for receiving the differential voltage output signal, the input end of the feedback amplifier connected in parallel to the differential voltage output signal, and an output end of the feedback amplifier coupled directly to the tail-current transistor for adjusting the current provided through each of the first and second electrical paths, wherein an input end of the feedback amplifier, being a feedback operational amplifier, includes a non-inverting input terminal and an inverting input terminal, each terminal coupled directly to one or the other of the output nodes of the single first and second transistors, the output nodes of the single stage differential amplifier are connected to two first conductive lines for directly outputting the differential voltage output signal to an external location from the single stage differential amplifier, and the output nodes of the single stage differential amplifier are connected to two second conductive lines for directly sending the differential voltage output signal to the input end of the feedback amplifier.