A CMOS continuous-time FPAA analog core using automatically-tuned MOS resistors

In this paper, a novel CMOS analog core for continuous-time FPAAs (field programmable analog arrays) is proposed. The proposed analog core consists of CMOS opamps and automatically-tuned MOS resistors. Since MOS resistor values are fixed by a PLL (phase locked loop) technique, the MOS resistors are almost immune to temperature variations and fabrication tolerances. In this analog core, the MOS resistors not only act as linear resistors but also as analog switches.