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3 I meant collector not base there.
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I'm reading through The Art of Electronics, and I'm trying to wrap my head around a Schmitt trigger.

Schematic

simulate this circuit – Schematic created using CircuitLab

Why is there no current over Q2 when Q1 is oversaturated? I see two paths out of R2 to R1 and in linear circuits there would be some current over both.

I'd assume it is because current from base to emitter in Q1 is oversaturating Q1 so it 'shorts' collector and emitter while dynamic resistance between basecollector and emitter is high so for near 0 V the Q2 behaves as if it was open (just as in silicon diodes). But I cannot find anything that would support this interpretation in the book (I probably missed something) outside "transistor man" model containing diode.

I'm reading through The Art of Electronics, and I'm trying to wrap my head around a Schmitt trigger.

Schematic

simulate this circuit – Schematic created using CircuitLab

Why is there no current over Q2 when Q1 is oversaturated? I see two paths out of R2 to R1 and in linear circuits there would be some current over both.

I'd assume it is because current from base to emitter in Q1 is oversaturating Q1 so it 'shorts' collector and emitter while dynamic resistance between base and emitter is high so for near 0 V the Q2 behaves as if it was open (just as in silicon diodes). But I cannot find anything that would support this interpretation in the book (I probably missed something) outside "transistor man" model containing diode.

I'm reading through The Art of Electronics, and I'm trying to wrap my head around a Schmitt trigger.

Schematic

simulate this circuit – Schematic created using CircuitLab

Why is there no current over Q2 when Q1 is oversaturated? I see two paths out of R2 to R1 and in linear circuits there would be some current over both.

I'd assume it is because current from base to emitter in Q1 is oversaturating Q1 so it 'shorts' collector and emitter while dynamic resistance between collector and emitter is high so for near 0 V the Q2 behaves as if it was open (just as in silicon diodes). But I cannot find anything that would support this interpretation in the book (I probably missed something) outside "transistor man" model containing diode.

2 Copy edited.
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Schmitt trigger - why there is there no current over the second transistor?

I'm reading through 'The Art of Electronics'The Art of Electronics, and I'm trying to wrap my head around a Schmitt trigger.

schematicSchematic

simulate this circuit – Schematic created using CircuitLab

Why when Q1 is oversaturated there is no current over Q2 when Q1 is oversaturated? I see two paths out of R2 to R1 and in linear circuits there would be some current over both.

I'd assume it is because current from base to emitter in Q1 is oversaturating Q1 so it 'shorts' collector and emitter while dynamic resistance between base and emitter is high so for near 0V0 V the Q2 behaves as if it was open (just as in silicon diodes). But I cannot find anything that would support this interpretation in the book (I probably missed something) outside "transistor man" model containing diode.

Schmitt trigger - why there is no current over the second transistor?

I'm reading through 'The Art of Electronics' and I'm trying to wrap my head around Schmitt trigger.

schematic

simulate this circuit – Schematic created using CircuitLab

Why when Q1 is oversaturated there is no current over Q2? I see two paths out of R2 to R1 and in linear circuits there would be some current over both.

I'd assume it is because current from base to emitter in Q1 is oversaturating Q1 so it 'shorts' collector and emitter while dynamic resistance between base and emitter is high so for near 0V the Q2 behaves as if it was open (just as in silicon diodes). But I cannot find anything that would support this interpretation in the book (I probably missed something) outside "transistor man" model containing diode.

Schmitt trigger - why is there no current over the second transistor?

I'm reading through The Art of Electronics, and I'm trying to wrap my head around a Schmitt trigger.

Schematic

simulate this circuit – Schematic created using CircuitLab

Why is there no current over Q2 when Q1 is oversaturated? I see two paths out of R2 to R1 and in linear circuits there would be some current over both.

I'd assume it is because current from base to emitter in Q1 is oversaturating Q1 so it 'shorts' collector and emitter while dynamic resistance between base and emitter is high so for near 0 V the Q2 behaves as if it was open (just as in silicon diodes). But I cannot find anything that would support this interpretation in the book (I probably missed something) outside "transistor man" model containing diode.

1
source | link

Schmitt trigger - why there is no current over the second transistor?

I'm reading through 'The Art of Electronics' and I'm trying to wrap my head around Schmitt trigger.

schematic

simulate this circuit – Schematic created using CircuitLab

Why when Q1 is oversaturated there is no current over Q2? I see two paths out of R2 to R1 and in linear circuits there would be some current over both.

I'd assume it is because current from base to emitter in Q1 is oversaturating Q1 so it 'shorts' collector and emitter while dynamic resistance between base and emitter is high so for near 0V the Q2 behaves as if it was open (just as in silicon diodes). But I cannot find anything that would support this interpretation in the book (I probably missed something) outside "transistor man" model containing diode.