New compact CMOS continuous-time low-Voltage analog rank-order filter architecture

A new compact CMOS continuous-time analog rank-order filter topology is presented. The hardware complexity grows linearly with the number of inputs at the rate of only two transistors per input. The implementation is based on a multiple input differential structure. The rank is programmable with the tail current source for all rank-order values from the Min to the Max case. The circuit has low voltage and low power consumption requirements. Experimental results are presented that verify the functionality and accuracy of the circuit. Simulation results show satisfactory operation in the 100-MHz frequency range for 0.5-μm CMOS technology and using a single 1.8-V supply. Two buffered versions of the circuit and efficient techniques for reduction of corner errors are also discussed.