Patent ID: 7812753

Claim:
A method for a rotation-based first order noise-shaping DEM technique for use with 3-level DAC unit elements comprising the following steps: (1) providing a multi-bit DAC, constructed from three-level state elements, wherein these state elements comprise a positive element, a negative element, and a mid-point element; (2) setting factor N=(number of analog levels of the DAC)−1; (3) setting NE pointer (last)=0; (4) setting a variable m=DAC digital input code (0<=m<=N); (5) calculating a reference S=2xm−N; (6) checking if S>0 and, if so, setting number of positive state elements to S and go to step (8), else go to step (7); (7) checking if S<0 and, if so, setting number of negative state elements to absolute value of |S|, else go directly to step (8); (8) setting number of mid-point state elements to absolute value of N−|S|; (9) rotating next element selection pointer by moving next element selection pointer to: NE pointer (new)=NE pointer (last)+|S| mod N; (10) checking if all DAC input codes are applied, and if so, go to step (11), else switch to next DAC input code m and go to step (4); and (11) exit.