A MULTIPLE-INPUT DIFFERENTIAL-AMPLIFIER BASED ON CHARGE SHARING ON A FLOATING-GATE MOSFET

The loseless property of an MOS floating gate is exploited to implemen t exact summing operations in the charge domain. Loseless charge shari ng in such structures yields circuits with potential applications as b uilding blocks for analog signal processing. Large signal as well as s mall signal models of floating-gate transistors are presented for both above-threshold and subthreshold regions. Experimental data from fabr icated devices in a 2 micron double poly, n-well process are in good a greement with the models. A canonical structure, the Multiple Input Fl oating-gate Differential Amplifier is proposed and its use in differen t circuit configurations demonstrated. Experimental data from a multip le differential input operational amplifier are presented. Limitations of the proposed circuits are also discussed.