A Built-in-Self-Test Scheme for Segmented and Binary Weighted DACs

This paper describes a new Built-In-Self-Test(BIST) scheme for estimation of static non-linearity errors in segmented and binary weighted digital to analog converters (DACs). The BIST scheme comprises of a hierarchy of tests including tests for non-monotonicity, checks to detect if the DNL/INL errors exceed ±0.5 LSB and actual estimation of the DNL/INL. The BIST scheme has been experimentally verified on 10-bit segmented current steering DAC. The DAC, along with the additional circuits required for testing, was designed and fabricated using a 0.35 m process. Both simulation and experimental results are included in this paper. Errors estimated using the BIST scheme match well with measurements done on the fabricated device.     

A new technique for on-chip error estimation and reconfiguration of current-steering digital-to-analog converters

In this paper, we propose a reconfigurable current-steering digital-to-analog converter (DAC). The differential nonlinearity error (DNL) of the DAC is estimated on-chip. This is used to reconfigure the switching sequence to get a lower integral nonlinearity error (INL). We propose a novel technique for estimation of DNL based on a step-size measurement. This greatly reduces the linearity and dynamic range requirements of the measuring circuits. A 10-b segmented DAC, along with the associated circuits for DNL estimation and reconfiguration, was designed using 0.35-/spl mu/m CMOS technology and fabricated through Europractice. The paper includes theoretical analysis, simulation, and experimental results for the proposed technique.