Hello List, Hello Ference! Regarding the topics we had today in the Mumble session: 1. here is a small discussion about the Schmitt-Trigger I had in mind, which points also to *both* sources I am aware of https://electronics.stackexchange.com/questions/301158/cmos-schmitt-trigger-... 2. attached a data book scan regarding TTL input current (I_iL, I_iH) - sorry in German only - for some TTL families. While nobody is using 74xx anymore, I guess we should be comparable to a 74LSxx standard input-load with our TTL Input Pad. Best Regards, Hagen. -- support LibreSilicon to get back into the Clean Room https://www.gofundme.com/f/libresilicon-cleanroom-rent