Patent ID: 7952428

Claim:
A circuit, comprising: an instrumentation amplifier including a pair of buffered operational amplifiers that accept a pair of input signals, and a differential operational amplifier that outputs an output signal indicative of a difference between the pair of input signals; a dynamically adjustable low pass filter configured to provide band limiting of the output signal at frequencies greater than a cutoff frequency; at least one monitor configured to monitor a signal upstream of the instrumentation amplifier and/or a signal downstream of the instrumentation amplifier and output a monitor signal; wherein each of the buffered operational amplifiers and the differential operational amplifier are implemented as a multi-path amplifier that includes a low frequency path and a high frequency path between an input and an output of the operational amplifier; wherein each of the multi-path amplifiers includes a differential input transconductance stage within the low frequency path and a differential input transconductance stage within the high frequency path; wherein, within each of the multi-path amplifiers, the differential input transconductance stage of the high frequency path is configured to provide dynamically adjustable noise shaping by producing more noise but consuming less power than the differential input transconductance stage of the low frequency path above a crossover frequency; and a controller configured to receive at least one said monitor signal, wherein the controller is configured to dynamically adjust output voltage noise at frequencies greater than the crossover frequency of the multipath amplifiers and/or the cutoff frequency of the low pass filter based on at least one said monitor signal.