You may put a series impedance, though, like a capacitor, but this is tricky, as spikes get through the capacitor easier (lower impedance at higher frequencies). Francisco Bob Ammerman wrote: >If Vin - Vout = 400V then you have > >80ma * 400V > >= 32 watts > >This will take quite a heatsink! > >Bob Ammerman >RAm Systems > > >----- Original Message ----- >From: "Jan-Erik Soderholm XA (TN/PAC)" >To: >Sent: Tuesday, September 16, 2003 3:44 PM >Subject: [EE]: Mains connected linear voltage reg. > > > > >>Hi. >>Just come across some linear voltage regulators >>from ST Microelectronics called VB408 and VB409. >>They have a high input voltage range (400 and 580V), >>so they can be connected directly to rectified 110 >>or 220 V mains. They deliver a max of 40 or 80mA, so >>could easily feed a simple PIC circuit. >> >>http://us.st.com/stonline/books/pdf/docs/6421.pdf >>http://us.st.com/stonline/books/pdf/docs/6941.pdf >> >>The VB408 is $0.84 is single quantity at Mouser. >> >>(23.90 SEK from Farnell in Sweden, or aprox $2.90 !) >> >> >>Now, anyone looked at these ? Or any similar mains >>connected volt regulator ? Could be an alternative >>to the usual "cap-voltage-divider" used in low power >>mains connected microcontroller circuits maybe ? >> >>Jan-Erik. >> >>-- >>http://www.piclist.com hint: The PICList is archived three different >>ways. See http://www.piclist.com/#archives for details. >> >> >> > >-- >http://www.piclist.com hint: The PICList is archived three different >ways. See http://www.piclist.com/#archives for details. > >. > > > -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body