Results of A/D converter compensation with a VLSI chip

Error table compensation is one technique that can be used to improve the spurious free dynamic range of high speed A/D converters. This paper gives details of an error table compensator system that uses a VLSI chip incorporating a transversal filter programmed as a wideband differentiator, some additional on chip circuits, and a lookup table that is stored in external memory. The 10 GOPS transversal filter differentiator chip was designed and fabricated in a 0.35 /spl mu/m CMOS process, has programmable tap weights, and can operate at a maximum clock rate of 200 MHz. The results of this paper show that this error table compensation system is capable of providing up to 13 dB improvement in the dynamic range of typical high speed A/D converters. This may result in more reliable detection of weak signals of interest.