Patent ID: 7271651

Claim:
A two stage analog amplifier circuit, comprising: a first stage having an input device that receives an input signal at a first input gate, the first input gate having a thick gate oxide layer wherein the thickness of the thick gate oxide layer is chosen so that the first stage input device has a low input gate leakage current, the first stage producing a first stage output signal; and a second stage having a second input device that receives the first stage output signal at a second input gate, the second input gate having a thin gate oxide layer wherein the thickness of the thin gate oxide layer is less than the thickness of the thick gate oxide layer of the first input gate, wherein the first stage is a wideband amplifier having a first stage gain that is limited to enhance the first stage frequency response, wherein the second stage has a second stage gain that is greater than the first stage gain and the second stage gain is limited to enhance the second stage frequency response, and wherein the combined first stage gain and second stage gain meet a required system gain that is a product of the first stage gain and the second stage gain.