Advanced ADC architecture with built-in self programming logic

The architecture of a new analog-to-digital converter (ADC) with built-in self programmable nonlinear (NL) characteristic is suggested. The programming facility refers to the possibility of modifying, all discrete points of the characteristic to fit a requested profile. The proposed converter can be utilized to gain remarkable advantages in a wide variety of applications in the smart sensor area. In fact, it results in a fundamental block to obtain a new type of sensor with a self calibration (and recalibration) peculiarity and a digital code linear with the sensed quantity. In the paper the ADC internal architecture is presented, discussing the main design and implementation issues for a 10 bit prototype. Finally, a representative application is discussed which illustrates the effectiveness and usefulness of this device in the gas sensor area.