A Fully Dynamic 1st-Order $\Delta-\Delta\sum$ Modulator with a $\text{468mV}_{\mathrm{p}\mathrm{p}}$ Input Range for Electrical Impedance Tomography Systems

This paper presents an imaging IC with readout front-ends (RFEs) based on a 1
^st
-order
$\Delta-\Delta\Sigma$
modulator
$(\Delta-\Delta\Sigma \mathrm{M})$
for electrical-impedance-tomography (EIT) systems. This allows the utilization of the readout data from all the electrodes, including even the current - inj ecting electrodes, without saturation, thus achieving much higher imaging contrast. The proposed EIT system achieves an input range of 468
$\text{mV}_{\mathrm{p}\mathrm{p}}$
, corresponding to 1.56
$\mathrm{k}\Omega$
when using a maximum current of 150
$\mu \mathrm{A}_{\mathrm{p}\mathrm{k}}$