CMOS adjustable Schmitt triggers

Three adjustable Schmitt triggers for implementation in CMOS technology are presented: two semi-adjustable circuits using only six transistors and one fully adjustable circuit using a total of eight transistors. The most significant features of all three are the hysteresis adjustment, two operation modes as a comparator or Schmitt trigger, very small chip area, and very low static power consumption. The fully adjustable Schmitt trigger has been realized using a 3-μm CMOS technology, and experimental results are presented