METHOD AND APPARATUS FOR LOW POWER CONTINUOUS TIME DELTA SIGMA MODULATION

摘要

A Continuous Time Delta Sigma Modulator (CTDSM) comprising a set of opamp integrators and at least one feedback DAC is provided with an assistant connected between the input and output of at least one of the opamp integrators of the set to moderate the linearity and bandwidth requirements of the opamp integrators of the set and result in low power dissipation. The assistant comprises a transconductor adapted to moderate the current demanded from the set of opamp integrators and a replica DAC adapted to steer the moderated current. This assisted opamp technique may be used with both single bit and multi bit CTDSMs.