Hello everyone.
I am trying to protect a smps input 24V from anything but 0-25/26V. I have tried just a tvs diode in parallel with a regular diode and it worked, until i put 120VAC on it. then it fried the tvs. the regular diode takes care of all negative volts, but i think that tvs diodes fry above their clamping voltage right? well, i think that the crowbar circuit i see all over the web is the way to go b/c an scr can handle a lot of current and voltage...but i don't know how to size all of the components properly. I have attached a schematic and have started by picking out the SCR.
SCR: STMicro TN1625-1000G-TR.
I would like to know the order of the component selection and some methodology for finding suitable parts.
I am trying to protect a smps input 24V from anything but 0-25/26V. I have tried just a tvs diode in parallel with a regular diode and it worked, until i put 120VAC on it. then it fried the tvs. the regular diode takes care of all negative volts, but i think that tvs diodes fry above their clamping voltage right? well, i think that the crowbar circuit i see all over the web is the way to go b/c an scr can handle a lot of current and voltage...but i don't know how to size all of the components properly. I have attached a schematic and have started by picking out the SCR.
SCR: STMicro TN1625-1000G-TR.
I would like to know the order of the component selection and some methodology for finding suitable parts.
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