B. Blad et al., WAVE-FORM GENERATOR FOR ELECTRICAL-IMPEDANCE TOMOGRAPHY (EIT) USING LINEAR INTERPOLATION WITH MULTIPLYING D A CONVERTERS/, Journal of medical engineering & technology, 18(5), 1994, pp. 173-178
This paper describes the implementation of a multiplying digital-to-an
alogue (D/A) converter as a Programmable waveform generator to be used
in an electrical impedance tomography (EIT) system. Different digital
techniques of generation waveforms are considered and the advantages
and disadvantages of the chosen slope-plus-peedestal technique are Pre
sented. A wire-wrapped protoype system has been designed, and from mea
sured frequency spectra the total harmonic distortion can be calculate
d to values between 1.1 and 2.9% depending on frequency.