G+_Rud Dog Posted August 19, 2017 Share Posted August 19, 2017 Does anyone know of a schematic for this relay board? Pretty simple but would like to see what all they placed on the board. BTW seeing lots of these relays online stating they 3.3V relays and all of the ones found so far have 5VDC stamped on them? Link to comment Share on other sites More sharing options...
G+_Graham Evans Posted August 19, 2017 Share Posted August 19, 2017 All the instances of "JQC-3FF-S-Z" I've found are for 5v relays. However a quite often 5v relays will work perfectly fine at 3.3v. However for the sake of a few more pennies/cents I'd look for one built for the job. Link to comment Share on other sites More sharing options...
G+_Rud Dog Posted August 19, 2017 Author Share Posted August 19, 2017 Graham Evans Indeed, that was my goal and while searching noted what I stated above. A bit concerned will order the relay, with the 5VDC stamped on it, only to find out it will not switch when driven by a 3.3VDC source. Link to comment Share on other sites More sharing options...
G+_Giligain I. Posted August 20, 2017 Share Posted August 20, 2017 • If it doesn't trigger yet at 3v, you can always go this route: https://electronics.stackexchange.com/questions/81580/step-up-3-3v-to-5v-for-digital-i-o • or this: https://electronics.stackexchange.com/questions/56093/how-to-use-a-3v-output-to-control-a-5v-relay • or this: https://electronics.stackexchange.com/questions/213051/how-do-i-use-a-5v-relay-with-a-3-3v-arduino-pro-mini • and I saw this in one of my collections: https://plus.google.com/110690680341063574122/posts/Yq6SpCh6S3n Link to comment Share on other sites More sharing options...
G+_Jonathan Bennett Posted August 20, 2017 Share Posted August 20, 2017 Assuming these are similar to what I've seen... These have a transistor on board, allowing a 3.3 signal to switch the 5v relay. I have a couple dual relay versions in my office right now. The vcc on the right needs 5 volts, and gnd is for ground, of course, and the in pin allows switching using 3.3v. Link to comment Share on other sites More sharing options...
G+_Rud Dog Posted August 20, 2017 Author Share Posted August 20, 2017 Jonathan Bennett ,thank you find it interesting they have incorporated the circuit you mentioned. Guess publishing a schematic would hurt their sales. Link to comment Share on other sites More sharing options...
G+_Giligain I. Posted August 20, 2017 Share Posted August 20, 2017 • JQC-3FF datasheet: http://www.robotshop.com/media/files/PDF/datasheet-v1.0-dfr0017.pdf Nominal Voltage VDC 5 Pick-up Voltage VDC 3.80 Drop-out Voltage VDC 0.5 Max. allowable Voltage VDC 6.5 Link to comment Share on other sites More sharing options...
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