Example: SCHMTRIG
Schmitt-Trigger

System

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System excitation

The input is an impulse of 5V with a width of 0.2μs, the rise and fall time is 100μs.

Task

Compute the transient analysis for [inline math]s to check the waveform of the output voltage VA.

Assumptions

The Gummel-Poon model can be used for the transistors T1 and T2.

Results

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This figure shows the input and output waveforms.

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The last figure shows the transfer curve with hysteresis (VE to VA).

Data

The following data were generated by DYNAST for the above given system model. You can modify the model parameters and re-submit the data to DYNAST to receive new results.

  

Submodels

Origin

 [1] Hoefer E. E. E., Nielinger H.: SPICE – Analyseprogramm für elektronische Schaltungen mit Beispielen. Springer-Verlag Berlin Heidelgerg 1985, pp. 175–178.

A. Meyer: Fraunhofer Institute for Integrated Circuits, Dresden, 2005.

Revised by: L. Pravda, CTU Prague, 2007.

Last Update

August 13, 2007