A 10-bit 20-MHz CMOS A/D converter

10-bit 20-MHz CMOS A/D 변환기

  • Published : 1996.04.01

Abstract

In tis work, a three-stage pipelined A/D converter (ADC) was implemented to obtain 10-bit resolution at a conversion rate of 20 msamples/s for video applications. The ADC consists of three identical stages employing a mid-rise coding technique. The interstage errors such as offsets and clock feedthrough are digitally corrected in digitral logic by one overlapped bit between stages. The proposed ADC is optimized by adopting a unit-capacitor array architecture in the MDAC to improve the differential nonlinearity and the yield. Reduced power dissipation has been achieve dby using low-power latched comparators. The prototype was fabricated in a 0.8$\mu$m p-well CMOS technology. The ADC dissipates 160 mW at a 20 MHz clock rate with a 5 V single supply voltage and occupies a die area of 7 mm$^{2}$(2.7 mm $\times$ 2.6mm) including bonding pads and stand-alone internal bias circuit. The typical differential and integral nonlinarities of the prototype are less than $\pm$ 0.6 LSB and $\pm$ 1 LSB, respectively.

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