Method and apparatus for enhancing dynamic range in a digital-to-analog conversion circuit

Described herein is a method and apparatus for enhancing the dynamic range of a digital-to-analog conversion circuit. Dynamic range enhancement (DRE) is accomplished by modifying the gain of components of the circuit so that the gain of components generating noise is effectively reduced. In a circuit utilizing a plurality of 1-bit DACs, analog signal gain is decreased when the full nominal gain of the analog portion of the circuit is not needed to obtain a desired peak output amplitude. The reduction is accomplished by effectively "disconnecting" some of the plurality of 1-bit DACs. Some or all of the 1-bit DACs are configured to have a third or "tri-state" in which there is no connection to the normal two reference levels thus providing no output. If some portion of the 1-bit DACs is placed in the tri-state, both the signal and noise gain will be reduced.