NPN transistor base resistor voltage spikes?

[Agony]

Run the simulation and noticedthe unusual voltage spike inbetween theresistor and base.
Would it be a bleedthrough from the 12V on collector?

[MikeK]

Your third attachment is empty.

[Agony]

weird... this should do then:

[Agony]

Could it be a simulation error or a kind of inductive voltage spike?
Alltho its within limits and wouldnt  damage the transistor, and the extra current it would let through wouldnt be a problem in current case - its still unwanted.

How would you go about smoothing it out?
Was thinking of a zener with a low breakdown voltage (in that case 0.9V) right inbetween the resistor and base with one end grounded.
So it would ground any spikes.

https://www.circuitlab.com/circuit/p3uvb3/npn-transistor-switch/

Tho that resulted in a waveform that has slightly less voltage at the beginning of each cycle and a spike in current at the end.

[croberts]

Hello Agony

I ran the simulation and do not see the spikes. I attached the image.

[Agony]

yes, i currently added the D2 zener wit h around 0,9V of breakdown voltage so it grounds the spikes, if you remove/disconnect it, the spikes show up.

[w2aew]

This is most likely a defect in the model for the 2N2222 in the simulator.  Models aren't perfect, and some are less perfect than others, especially for modeling non-linear, large-signal behavior.