Analysis of Mismatch Effects in Matrix-Based Systems Using Dynamic Element Matching (Out of the Chains and into the Matrix?)

Abstract

The Dynamic Element Matching (DEM) technique's role is to mitigate mismatch issues in complex, matrix-based systems. In this paper, we explore the impact of partially applying DEM to the thermometrically encoded 10-bit most significant bits (MSBs) out of a high-resolution segmented 16-bit Digital-to-Analog Converter (DAC) with the least significant 6 bits being binary encoded. Specifically, we design a general purpose scalable digital control circuit able to employ the DEM algorithm, independent of the matrix dimensions. When implementing the proposed controller using a commercial 180 nm CMOS process, tailored to the 10-bit thermometric decoded DAC MSBs, the integral nonlinearity (INL) 12.63 times lower and the differential nonlinearity (DNL) is 5.8 times lower. The silicon area required for the additional circuitry is around 0.12 mm ², with a power consumption of up to 12.88 mA from a 1.8 V power supply when running at 100 MHz.