Discrete Transistor Schmitt Trigger

137

02:21:41

From 
http://www.johnhearfield.com/Eng/Schmitt.htm

Adapted for low power operation.  This designed for Vn at ~2.8V and Vp at ~3.5V.

A useful concept for introducing hysteresis.  Omit the base resistor of the leftmost BJT if the known driving voltage is known to have an acceptably high source impedance to apply to the base of the BJT.

published 10 years ago

roops1967

10 years ago

Thanks mate that is a educating read

jjmilburn

10 years ago

I thought so too! Note that in this schematic, the "7V" is the supply voltage, and the "3.53V" is the "input". To see the Schmitt trigger action (hysteresis), reduce the value of the 3.53V down below 2.8V.

roops1967

10 years ago

Yeah works great. Try AC

mrdouble

9 years ago

No solution :/

add comment in editor

EveryCircuit is an easy to use, highly interactive circuit simulator and schematic capture tool. Real-time circuit simulation, interactivity, and dynamic visualization make it a must have application for professionals and academia. EveryCircuit user community has collaboratively created the largest searchable library of circuit designs. EveryCircuit app runs online in popular browsers and on mobile phones and tablets, enabling you to capture design ideas and learn electronics on the go.