A 9.15mW 0.22mm<sup>2</sup> 10b 204MS/s pipelined SAR ADC in 65nm CMOS

Abstract

This paper describes a 10b 204MS/s analog-to-digital converter (ADC) employing a pipelined successive approximation register (SAR) architecture for low power consumption and small area. To improve the operation frequency, the pipelined SAR ADC consists of two channels with a proposed asynchronous timing technique. This technique increases the amplification time of a residue opamp. To reduce power and area, the opamp is shared between two channels. A reference buffer with a deglitch circuit reduces the glitch and settling time of reference voltages. The prototype ADC fabricated in a 65nm CMOS process shows a SNDR of 55.2dB and a SFDR of 63.5dB with a 2.4MHz input at 204MS/s. The ADC occupies 0.22mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> and dissipates 9.15mW at a 1.0V supply. The FoM of the ADC is 95.4fJ/conversion-step.