At 08:34 AM 3/15/2004, Andre Miller wrote: >Thanks for the circuit diagram! > >I still have one question though, how do I connect the AC supply and the 5V >DC supply together? > >Say I have a 24V transformer, which will drive the load, and I rectify / >regulate this to drive the PIC. Where is 'ground' in this case for the >rectified/regulated supply and where is ground for the two AC wires coming >out of the transformer? And do I just connect these two grounds together? > >Sorry if you've answered this already. (And apologies about my poor ASCII >art!). Are there any connections missing from the below schematic? And would >it work like that? I know the supply is missing some filter/smoothing caps. > > 7805 > A K ,----------. >-------)-+----------|>|---+----|IN G OUT|------ +5V to PIC > 24V AC } CAP `----+-----' >-------)------+-----------+---------+------------ GND to PIC > | | 470 uF 50V > | | ____ > | | ------------|____|-------------- Trigger from PIC > | _|_/ Rg > | V_A > | | > C| | >Solonoid C| | > C| | > | | > +----+ Easy - don't use a bridge rectifier. Use a single diode as a half-wave rectifier. Look at it this way: the PIC and its associated circuitry does not consume much current (5 - 20 mA). You can tolerate a lot of ripple going into the regulator with no problems. Most of my 24 Vac stuff doesn't even use an IC regulator - just a simple series resistor / zener shunt regulator. dwayne -- Dwayne Reid Trinity Electronics Systems Ltd Edmonton, AB, CANADA (780) 489-3199 voice (780) 487-6397 fax Celebrating 20 years of Engineering Innovation (1984 - 2004) .-. .-. .-. .-. .-. .-. .-. .-. .-. .- `-' `-' `-' `-' `-' `-' `-' `-' `-' Do NOT send unsolicited commercial email to this email address. This message neither grants consent to receive unsolicited commercial email nor is intended to solicit commercial email. -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body