Patent ID: 8724355

Claim:
A multi-stage rectification and amplification circuit comprising a plurality of stages of rectification and amplification circuits, each rectification and amplification circuit generating a rectified current and an amplified voltage, the rectification and amplification circuit of each stage comprising: a first transconductor and a second transconductor configured to: receive a first input voltage V in — a and a second input voltage V in — b respectively; and convert a differential voltage between the first input voltage and the second input voltage to intermediate currents, the sum of intermediate currents having a magnitude of a tail current being provided by a first current source and a second current source connected to the first transconductor and the second transconductor respectively; a rectifying means configured to convert the differential voltage (V in — a −V in — b ) into the intermediate currents and selectively sum the intermediate currents to obtain the rectified current; and an amplifying means configured to amplify the differential voltage (V in — a −V in — b ) to the amplified voltage, the amplified voltage corresponding to the difference between a first output voltage and a second output voltage (V out — a −V out — b ) wherein the rectified currents of the rectification and amplification circuit of the each stage being aggregated to provide a total rectified current, the first output voltage and the second output voltage of the rectification and amplification circuit of the each stage being provided as the first input voltage V in — a and the second input voltage V in — b to the rectification and amplification circuit of a subsequent stage, and the rectification circuit and amplification circuit of the each stage having substantially similar gain and rectification range.