This paper presents a dynamic element matching (DEM) decoder
incorporating both intersymbol interference (ISI) and mismatch error
shaping. From the analysis of ISI error in multi-bit DACs, an algorithm
is developed that deterministically controls the element transitions,
such that on each conversion cycle the instantaneous number of on
transitions is set to a constant value, while the instantaneous number
of off transitions varies with the decoder input signal. The technique
achieves greater ISI error mitigation than previous approaches using
less hardware. To further reduce the logic area, a hierarchical DEM
structure, whereby the DEM decoder is split into multiple sub-DEM
decoders, is presented.