Micro-controller based active electrodes for impedance tomography

An active electrode circuit for EIT is described. The circuit uses a micro-controller to implement a simple protocol for communicating with the data-acquisition system. This allows the active electrode to obtain configuration data (address of the electrode and number of electrodes present) from which it can determine, algorithmically, the function (current source/sink, voltage follower/inverter, disconnected) it is to perform at each step of the data acquisition sequence.<>