Here you go. Now probe the base current. Admittedly the generic NPN model is unrealistic, but I bet you find its, erm, a lot bigGA than you expect.
Edit: As you will see in the second graph, the apparent base current is ridiculously big. Of course, in practice the current would be less, but the transistor would surely fail. The collector voltage is more interesting with this triangular waveform. For base voltages above about 1.5V normal saturated behaviour breaks down, or at least the model behaviour suggests that it does.
The remedy for this is simple, fit a base series resistor. The final graph shows a result with this done.
Edit: As you will see in the second graph, the apparent base current is ridiculously big. Of course, in practice the current would be less, but the transistor would surely fail. The collector voltage is more interesting with this triangular waveform. For base voltages above about 1.5V normal saturated behaviour breaks down, or at least the model behaviour suggests that it does.
The remedy for this is simple, fit a base series resistor. The final graph shows a result with this done.
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