Patent ID: 7358810

Claim:
A buffer amplifier comprising: a first differential signal amplifier comprising first and second N-type metal-oxide semiconductor field-effect transistors (NMOSFETs) which amplifies differential input signals; a second differential signal amplifier comprising first and second P-type metal-oxide semiconductor field-effect transistors (PMOSFET) which amplifies the differential input signals; a first feedback resistor comprising an end commonly connected to drains of the first NMOSFET and the first PMOSFET and another end commonly connected to gates of the first NMOSFET and the first PMOSFET; a second feedback resistor comprising an end commonly connected to drains of the second NMOSFET and the second PMOSFET and another end commonly connected to gates of the second NMOSFET and the second PMOSFET; and a current source which provides a bias current for driving the first and second differential signal amplifiers.