Adjustable Schmitt triggers using floating-gate MOS transistors

Novel Schmitt triggers based on multiple-input floating-gate MOS(FGMOS) transistors are presented. By using the control signal of multiple-input gate, the adjustable threshold voltages can be achieved conveniently. As the variable threshold voltage can be achieved easily in FGMOS circuit, all the proposed Schmitt triggers have considerable simpler structure. The effectiveness of the proposed Schmitt triggers has been validated by HSPICE simulation results with TSMC 0.35μm 2-ploy 4-metal CMOS technology.