CMOS switch Schmitt trigger - an unusual use for an electronic switch

CMOS switch Schmitt trigger It is generally accepted that a CMOS analogue switch (type 4066) can only be used as an electronic substitute for switching low power signals. However, this is not strictly true. It is also possible to use a single CMOS switch an unusual use for an electronic switch 1 becomes dependent on the trigger voltage level. Applications include limiting circuitry and auto-ranging. It is advisable to ensure that the input voltage to the CMOS switch does not drop below 3 V. ES = "A 4066 B ES = "A 4066 B 82509-1 as a Schmitt trigger. This can be very useful as, if a Schmitt trigger is required and not all of the CMOS switches available in a single IC have been used, the circuit in figure 1 can be used to avoid the expense of an extra IC. The resistor values required for the Schmitt trigger can be 2 calculated as follows: 0 to 1 transition threshold = Ub • (1 + -) 1 to 0 transition R1 threshold = Ub • (1 - - ) R2 An interesting variation of the circuit is ...