Static Characterization of High Resolution DAC Based on Over Sampling and Low Resolution ADC

A new method is presented for the static characterization of high resolution digital to analog converters (DAC). The method is based on the comparison of the DAC output voltage signal with a reference one furnished by a calibrator instrument. The zero crossing sequence of the resulting signal is detected by over sampling in order to avoid the amplitude measurement. The variation in the time domain of the zero crossing sequence distribution respect to that occurring in the sinusoidal reference signal is used to evaluate the DAC transfer characteristic, the INL and the DNL. The advantage of the method consists in the fact that the analog to digital converter to be used to acquire the resulting signal can be characterized by a lower resolution respect to the DAC under test. The numerical and experimental tests confirm the potentiality of the method and the advantages in term of time reduction.