A CMOS 8-bit two-step A/D converter with low power consumption

A low cost 8-bit A/D converter based on two-step flash topology is presented in this paper. The design, process technology, and performance of this A/D converter will be described. In order to achieve high precision and low power, a corrected chopper-type comparator which can completed sampling comparison and subtraction has been introduced. The designed A/D converter is fabricated in 0.6 mu m CMOS double-polysilicon and double-metal process technology and occupies an active area of 1.1 mm(2). The measurement results show that the design offers a 133 ns conversion time and dissipates only 6 mW power dissipation at 3 V power supply and 30 mW power dissipation at 5 V power supply separately with 5MHz sampling rate.