Hardware realization of analog CMOS current-mode minimum circuit

Abstract

Fuzzy systems can be implemented by software or hardware. The software approach is complex and its operation speed is low particularly in real-time applications. On the other hand, the hardware implementations (digital and/or analog) of fuzzy systems yield high speed and high efficiency for real-time applications. Since fuzzy systems normally have output with amplitude that varies continuously from 0 to 1, then the analog implementation is the most suitable choice. Besides, analog circuits have higher speed and lower power consumption than their digital counterparts. In this paper, a new current mode, multiple input minimum circuit is proposed. It has many features such as high speed, small area, low power dissipation and compatibility with VLSI implementation. Also, the circuit does not need any preprocessing (normalization) of the input currents before calculating the minimum. These features make it suitable as a building block in real-time computational systems such as fuzzy or artificial neural networks.