Patent ID: 7019586

Claim:
An apparatus to tune a tunable Gm-C circuit, the apparatus comprising: a master Gm-C circuit comprising a transconductance and a tunable element, wherein the master Gm-C circuit is configured to provide a waveform that is dependent on a tuning signal applied to the tunable element; a first signal generator to generate a first clock signal; a second signal generator to provide a second clock signal to the master Gm-C circuit; a sampler having a first input coupled to receive the waveform from the master Gm-C circuit, a second input coupled to receive the first clock signal, a third input coupled to receive the second clock signal, and an output to provide a tuning error signal; and a tuning control stage having an input coupled to the output of the sampler and having an output to provide the tuning signal to the master Gm-C circuit and to the tunable Gm-C circuit.