Abstract : For the digital signal processing (DSP) part of mixed-signal systems, fixed-point arithmetic is favoured due to its high efficiency in terms of implementation cost, namely energy consumption, area, and latency. Fixed-point arithmetic provides low-cost operators at the expense of an unavoidable error between the ideal precision values and the finite precision ones. With a careful data word-length optimisation process, the designer can safely profit from the inherent trade-off between implementation cost and computation accuracy. In this chapter, we describe in detail the different stages comprising the fixed-point conversion process (i.e., dynamic range evaluation, word-length optimisation, and accuracy evaluation) and propose practical solutions to address each stage.
