.BondLib.Examples.ModelicaSpice.DifferentialAmplifier

Differential amplifier circuit made from two p-channel JFETs

Information

This circuit describes a differential amplifier built from two p-channel JFETs. Notice the use of ramping sources. After ramping, the gate of the right JFET is held constant at 0.5 Volt, whereas the gate of the left JFET varies slightly around that value using a sine-wave. The output voltage inverts and amplifies that differential voltage by about a factor of 80.

Simulate the circuit across 0.005 seconds and plot the input and output voltages as functions of time.

This example does not currently simulate. It simulated correctly under Dymola 6.0b with Modelica 2.2, but in Dymola 6.1 with Modelica 2.2.1, the simulation dies at time 0, claiming that a Newton iteration on a non-linear set of equations fails to converge.

We are still investigating what the cause of this anomaly is.

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