Hi,
I am a beginner HW designer (student at the moment). I have a little circuit involving LM393 comparator and a thyristor that I have to turn under certain conditions...
The idea is that when that condition is met, the LM393 outputs logical one, which should trigger the thyristor (BT169D). I added a simple transistor stage just to make sure the triggering signal for the thyristor gate has enough voltage and current. However, the thyristor turns on right after the supply voltage is applied to the circuit... Have you got any ideas, how could I fix it? Circuit in the attachments.
I made sure my wiring is correct.
The LM393 does not output a high signal right after the power on. LM393 has a default logical zero output state (I verified it with measurements.)
Thank you in advance

I am a beginner HW designer (student at the moment). I have a little circuit involving LM393 comparator and a thyristor that I have to turn under certain conditions...
The idea is that when that condition is met, the LM393 outputs logical one, which should trigger the thyristor (BT169D). I added a simple transistor stage just to make sure the triggering signal for the thyristor gate has enough voltage and current. However, the thyristor turns on right after the supply voltage is applied to the circuit... Have you got any ideas, how could I fix it? Circuit in the attachments.
I made sure my wiring is correct.
The LM393 does not output a high signal right after the power on. LM393 has a default logical zero output state (I verified it with measurements.)
Thank you in advance

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