I am VERY interested in checking out this chip, and others like it. But so far, I am unable to locate ANY suppliers of it. The Harris chips mentioned previously, are no longer in production (so I've been told). The VB409 is a relitively new semiconductor, so I would assume they are still making it. I've already checked out the usual suspects (digikey, mouser, jameco, etc..), without any luck. I've tried to contact ST directly, but they haven't gotten back to me (And from previous experience, they probably won't either). Any help locating a supplier for this part would be greatly appreciated Thanks in advance. Pat op1cwk@flashmail.com -----Original Message----- From: V sml To: PICLIST@MITVMA.MIT.EDU Date: Friday, September 15, 2000 12:27 PM Subject: Re: [EE]: 5V DC from 220V AC supply without a transformer? >I posted the brief description and link a while back, they are listed >below again. Hope it is helpful. Beware that there is no galvanic >insulation, and be careful too. > >Cheers, Ling SM (not related to STm) > >http://www.st.com/stonline/prodpres/discrete/vipower/vb409/vb409.htm > > >The VB409 VB409SP are fully protected positive >voltage regulator designed in STMicroelectronics >High Voltage VIPower] technology. The devices >can be connected directly to the rectified mains >(110V/230V). The devices are well suited for >applications powered from the AC mains and >requiring a 5V DC regulated output voltage >without galvanic insulation. VB409, VB409SP >provides up to 70 mA output current (internally >limited) at 5V. The included over current and >thermal shutdown provide protection for the >device. > >> > Someone told me a while ago that I can do without the expensive = >> > transformer, diode bridge and regulator to get 5V power from a >220 - = >> > 250V AC line to drive a PIC with some other components like a >relay, = >> > triac, leds etc.=20 >> > >> > I remember them talk about caps and zeners..=20 >> > >> > (I am use to the XFormer and the well known 78L05 method) >> > >> > Can sombody help me with a plan >> >> Microchip has a application note on a transformless power supply. >The PDF >can >> be found here: >> >> http://search1.microchip.com/ie/appnote/category/pic16/91008a.pdf >> >> Now here's my stearn warning in all caps: >> >> NOTE THAT THIS DESIGN AS WITH ALL TRANSFORMERLESS DESIGNS HAVE A >DIRECT >> CONNECTION TO THE HOT AC LINE. CARELESS HANDLING OF SUCH A CIRCUIT >CAN >RESULT >> IN SERIOUS INJURY OR DEATH! TREAT ALL PARTS OF THE CIRCUIT AND ANY >DEVICES >> CONNECTED TO IT AS HIGH VOLTAGE AC! >> >> Note you'll have to pay attention to the reactance of the cap >because the >> voltage is doubled. >> >> Good Luck. >> >> BAJ >> >> -- >> http://www.piclist.com hint: The list server can filter out >subtopics >> (like ads or off topics) for you. See http://www.piclist.com/#topics >> >> > >-- >http://www.piclist.com hint: The list server can filter out subtopics >(like ads or off topics) for you. See http://www.piclist.com/#topics > >-- >http://www.piclist.com hint: The list server can filter out subtopics >(like ads or off topics) for you. See http://www.piclist.com/#topics > > > -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu