Vol. IV — Electronics · Tool
Ideal rails only. A plain comparator flips at one threshold. A Schmitt trigger adds hysteresis so noise does not chatter the output. Change Vin, Vref, rails, and R1 / R2 — thresholds and HIGH / LOW update as you type.
Comparator: Vout rails to Voh when Vin > Vref, and to Vol when Vin < Vref (ideal, no open-loop gain). Equal inputs stay at the last state for this demo.
Inverting Schmitt: positive feedback through R1 (from output) and R2 (to the signal / ground node). Thresholds sit at β·Voh and β·Vol where β = R2 / (R1 + R2) for the classic divider on the + input while Vin drives the − input — crossing either way flips the rail and the threshold jumps the other way. Hysteresis width is |Vth_high − Vth_low|.
Non-inverting Schmitt: Vin into the divider with R1 to the + node and R2 back from the output; thresholds become weighted mixes of Vin and the rails. Pair with Op-amp gain, the voltage divider, and the electronics bench.