On Tue, 17 Apr 2018 05:53:36 -0000 (UTC), Jasen Betts <jasen@xnet.co.nz> wrote:>On 2018-04-16, George Herold <gherold@teachspin.com> wrote: > >> I started here, (of course) >> http://www.analog.com/media/en/technical-documentation/application-notes/AN118fb.pdf >> Figure 13 looked nice. I then priced a pico 32195 transformer. >> ~$100! Ouch! (maybe I can find a cheaper one.) > >that should be possible PC powersupplies have one for stepping about 350V down to >5V at about 2-10W as do many wall-warts. these transformers can be run in reverse. > >digikey has a bunch of transformwers for a few bucks each >https://www.digikey.com/products/en/inductors-coils-chokes/arrays-signal-transformers/73 >dunno why they call them sifnal transformers. the parameters are series >and parallel incuctance, but if you havce a spice parameters for the part >you want you can probably find a close match using those numbers. > >> Oh over the weekend I was thinking about making a C-W generator, >> (mostly because I always wanted to.) I was going to make my own >> oscillator ~10-100 kHz, boost the voltage with a transformer >> and send it into a CW network. Sounds fun, but a lot of work. > >Yeah, for C-W you need a symmetrical output like Baxandall, if you >just want to step up you can use a flyback converter which is simpler. > >> Oh finally I can buy DC-DC converters from pico electronics for >> ~$100. >> https://www.picoelectronics.com/high-voltage-low-power-dc-dc-converters > >Seems to spoil all the fun. I guess it depends whether you want to >learn or to do.Most any waveform will pump a C-W string. That includes a low-duty-cycle flyback. https://www.dropbox.com/s/sokhhr8yibzdkt6/T840_A13_PS.pdf?raw=1 https://www.dropbox.com/s/lbemdfl85qbd255/ALX_DRQ_5.asc?dl=0 -- John Larkin Highland Technology, Inc lunatic fringe electronics
300V power supply.
Started by ●April 16, 2018
Reply by ●April 17, 20182018-04-17
Reply by ●April 17, 20182018-04-17
On Tue, 17 Apr 2018 07:09:07 -0700 (PDT), George Herold <gherold@teachspin.com> wrote:>On Tuesday, April 17, 2018 at 8:58:07 AM UTC-4, bill....@ieee.org wrote: >> On Tuesday, April 17, 2018 at 4:01:17 PM UTC+10, Jasen Betts wrote: >> > On 2018-04-16, George Herold <gherold@teachspin.com> wrote: >> > >> > > I started here, (of course) >> > > http://www.analog.com/media/en/technical-documentation/application-notes/AN118fb.pdf >> > > Figure 13 looked nice. I then priced a pico 32195 transformer. >> > > ~$100! Ouch! (maybe I can find a cheaper one.) >> > >> > that should be possible PC powersupplies have one for stepping about 350V down to >> > 5V at about 2-10W as do many wall-warts. these transformers can be run in reverse. >> > >> > digikey has a bunch of transformwers for a few bucks each >> > https://www.digikey.com/products/en/inductors-coils-chokes/arrays-signal-transformers/73 >> > dunno why they call them sifnal transformers. the parameters are series >> > and parallel incuctance, but if you havce a spice parameters for the part >> > you want you can probably find a close match using those numbers. >> > >> > > Oh over the weekend I was thinking about making a C-W generator, >> > > (mostly because I always wanted to.) I was going to make my own >> > > oscillator ~10-100 kHz, boost the voltage with a transformer >> > > and send it into a CW network. Sounds fun, but a lot of work. >> > >> > Yeah, for C-W you need a symmetrical output like Baxandall, if you >> > just want to step up you can use a flyback converter which is simpler. >> >> The regular Baxandall circuit always produces a sine wave with a couple of percent of harmonic content. I've got a less efficient version - 50% rather than 95% - where the harmonic content can be a couple of orders of magnitude lower. >> >> -- >> Bill Sloman, Sydney > >Yeah I've mostly given up the C-W dream for now. At ~300V it looks like >a flyback is a cheaper/ easier option. > >George h.It would be fun to make a big CW, like a megavolt or something. A string of cheap PC boards could do that. -- John Larkin Highland Technology, Inc lunatic fringe electronics
Reply by ●April 17, 20182018-04-17
On Tuesday, April 17, 2018 at 11:29:19 AM UTC-4, John Larkin wrote:> On Tue, 17 Apr 2018 07:09:07 -0700 (PDT), George Herold > <gherold@teachspin.com> wrote: > > >On Tuesday, April 17, 2018 at 8:58:07 AM UTC-4, bill....@ieee.org wrote: > >> On Tuesday, April 17, 2018 at 4:01:17 PM UTC+10, Jasen Betts wrote: > >> > On 2018-04-16, George Herold <gherold@teachspin.com> wrote: > >> > > >> > > I started here, (of course) > >> > > http://www.analog.com/media/en/technical-documentation/application-notes/AN118fb.pdf > >> > > Figure 13 looked nice. I then priced a pico 32195 transformer. > >> > > ~$100! Ouch! (maybe I can find a cheaper one.) > >> > > >> > that should be possible PC powersupplies have one for stepping about 350V down to > >> > 5V at about 2-10W as do many wall-warts. these transformers can be run in reverse. > >> > > >> > digikey has a bunch of transformwers for a few bucks each > >> > https://www.digikey.com/products/en/inductors-coils-chokes/arrays-signal-transformers/73 > >> > dunno why they call them sifnal transformers. the parameters are series > >> > and parallel incuctance, but if you havce a spice parameters for the part > >> > you want you can probably find a close match using those numbers. > >> > > >> > > Oh over the weekend I was thinking about making a C-W generator, > >> > > (mostly because I always wanted to.) I was going to make my own > >> > > oscillator ~10-100 kHz, boost the voltage with a transformer > >> > > and send it into a CW network. Sounds fun, but a lot of work. > >> > > >> > Yeah, for C-W you need a symmetrical output like Baxandall, if you > >> > just want to step up you can use a flyback converter which is simpler. > >> > >> The regular Baxandall circuit always produces a sine wave with a couple of percent of harmonic content. I've got a less efficient version - 50% rather than 95% - where the harmonic content can be a couple of orders of magnitude lower. > >> > >> -- > >> Bill Sloman, Sydney > > > >Yeah I've mostly given up the C-W dream for now. At ~300V it looks like > >a flyback is a cheaper/ easier option. > > > >George h. > > It would be fun to make a big CW, like a megavolt or something. A > string of cheap PC boards could do that. >I'm not sure what you mean by a string of PC boards. I've got this guys book, where he makes a 250 kV C-W. http://www.diyphysics.com/2012/02/09/d-i-y-250-kv-high-voltage-dc-power-supply-with-neat-trick-for-switching-polarity/#more-614 I think you need to start worrying about x-rays at those voltages. Oh, the UCSB fel runs off a huge Van de Graff. (I guess it's real name is a pelletron.) http://sbfel3.ucsb.edu/ George H.> > -- > > John Larkin Highland Technology, Inc > > lunatic fringe electronics
Reply by ●April 17, 20182018-04-17
On Tuesday, April 17, 2018 at 11:27:19 AM UTC-4, John Larkin wrote:> On Tue, 17 Apr 2018 05:53:36 -0000 (UTC), Jasen Betts > <jasen@xnet.co.nz> wrote: > > >On 2018-04-16, George Herold <gherold@teachspin.com> wrote: > > > >> I started here, (of course) > >> http://www.analog.com/media/en/technical-documentation/application-notes/AN118fb.pdf > >> Figure 13 looked nice. I then priced a pico 32195 transformer. > >> ~$100! Ouch! (maybe I can find a cheaper one.) > > > >that should be possible PC powersupplies have one for stepping about 350V down to > >5V at about 2-10W as do many wall-warts. these transformers can be run in reverse. > > > >digikey has a bunch of transformwers for a few bucks each > >https://www.digikey.com/products/en/inductors-coils-chokes/arrays-signal-transformers/73 > >dunno why they call them sifnal transformers. the parameters are series > >and parallel incuctance, but if you havce a spice parameters for the part > >you want you can probably find a close match using those numbers. > > > >> Oh over the weekend I was thinking about making a C-W generator, > >> (mostly because I always wanted to.) I was going to make my own > >> oscillator ~10-100 kHz, boost the voltage with a transformer > >> and send it into a CW network. Sounds fun, but a lot of work. > > > >Yeah, for C-W you need a symmetrical output like Baxandall, if you > >just want to step up you can use a flyback converter which is simpler. > > > >> Oh finally I can buy DC-DC converters from pico electronics for > >> ~$100. > >> https://www.picoelectronics.com/high-voltage-low-power-dc-dc-converters > > > >Seems to spoil all the fun. I guess it depends whether you want to > >learn or to do. > > Most any waveform will pump a C-W string. That includes a > low-duty-cycle flyback. > > https://www.dropbox.com/s/sokhhr8yibzdkt6/T840_A13_PS.pdf?raw=1 > > https://www.dropbox.com/s/lbemdfl85qbd255/ALX_DRQ_5.asc?dl=0Oh that saves me some time! Thanks. GH> > > -- > > John Larkin Highland Technology, Inc > > lunatic fringe electronics
Reply by ●April 17, 20182018-04-17
On Mon, 16 Apr 2018 10:49:40 -0700, George Herold wrote:> Oh over the weekend I was thinking about making a C-W generator, > (mostly because I always wanted to.) I was going to make my own > oscillator ~10-100 kHz, boost the voltage with a transformer and send it > into a CW network. Sounds fun, but a lot of work.Er, no it isn't. It *really* isn't. -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.
Reply by ●April 17, 20182018-04-17
On Tue, 17 Apr 2018 10:10:31 -0700 (PDT), George Herold <gherold@teachspin.com> wrote:>On Tuesday, April 17, 2018 at 11:27:19 AM UTC-4, John Larkin wrote: >> On Tue, 17 Apr 2018 05:53:36 -0000 (UTC), Jasen Betts >> <jasen@xnet.co.nz> wrote: >> >> >On 2018-04-16, George Herold <gherold@teachspin.com> wrote: >> > >> >> I started here, (of course) >> >> http://www.analog.com/media/en/technical-documentation/application-notes/AN118fb.pdf >> >> Figure 13 looked nice. I then priced a pico 32195 transformer. >> >> ~$100! Ouch! (maybe I can find a cheaper one.) >> > >> >that should be possible PC powersupplies have one for stepping about 350V down to >> >5V at about 2-10W as do many wall-warts. these transformers can be run in reverse. >> > >> >digikey has a bunch of transformwers for a few bucks each >> >https://www.digikey.com/products/en/inductors-coils-chokes/arrays-signal-transformers/73 >> >dunno why they call them sifnal transformers. the parameters are series >> >and parallel incuctance, but if you havce a spice parameters for the part >> >you want you can probably find a close match using those numbers. >> > >> >> Oh over the weekend I was thinking about making a C-W generator, >> >> (mostly because I always wanted to.) I was going to make my own >> >> oscillator ~10-100 kHz, boost the voltage with a transformer >> >> and send it into a CW network. Sounds fun, but a lot of work. >> > >> >Yeah, for C-W you need a symmetrical output like Baxandall, if you >> >just want to step up you can use a flyback converter which is simpler. >> > >> >> Oh finally I can buy DC-DC converters from pico electronics for >> >> ~$100. >> >> https://www.picoelectronics.com/high-voltage-low-power-dc-dc-converters >> > >> >Seems to spoil all the fun. I guess it depends whether you want to >> >learn or to do. >> >> Most any waveform will pump a C-W string. That includes a >> low-duty-cycle flyback. >> >> https://www.dropbox.com/s/sokhhr8yibzdkt6/T840_A13_PS.pdf?raw=1 >> >> https://www.dropbox.com/s/lbemdfl85qbd255/ALX_DRQ_5.asc?dl=0 >Oh that saves me some time! Thanks. >GHThat LTC chip is not very expensive, and the simulation seems to work accurately. Unless you are going to make many thousand units, the chip is worth it. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
Reply by ●April 17, 20182018-04-17
On Monday, April 16, 2018 at 4:02:31 PM UTC-4, John Larkin wrote:> On Mon, 16 Apr 2018 10:49:40 -0700 (PDT), George Herold > <gherold@teachspin.com> wrote: > > >Hi all, So I'd like to make a 300 V supply. I don't really want to start from > >the AC line. So I've been looking for a DC-DC converter solution. > > > >I started here, (of course) > >http://www.analog.com/media/en/technical-documentation/application-notes/AN118fb.pdf > >Figure 13 looked nice. I then priced a pico 32195 transformer. > >~$100! Ouch! (maybe I can find a cheaper one.) > > Pico is insane. I don't know why anybody buys their stuff.Maybe you missed the part about high reliability, ruggedization, burn-in and cycling test. These are better than militarized. And they're going to cost. "Pico Electronics, Inc. is the industry leader for manufacturing high reliability miniature and ultra-miniature passive magnetic components. From the depths of the oceans, to the surface of Mars, Pico’s transformers and inductors are used in the most rugged applications. Many Pico Transformers and Inductors have passed 300 thermal cycles and have been exposed to a variety of temperature extremes. Our products have been engineered, and designed into, applications throughout the Aerospace, Defense, Space, and Commercial Industries. Where a design demands reliability, when size and weight constraints are a factor, Pico Electronics’ products are the solution."> > How much current do you want? The lower section of this will do 300 > volts. > > https://www.dropbox.com/s/e3n5af9sw1a1flh/28S840A_3.pdf?raw=1 > > Just skip the C-W HV stuff. > > You could also buy some cheap (like $4) DC/DC converter bricks and put > the outputs in series. Stack them on top of whatever power rail you > already have. > > > > > -- > > John Larkin Highland Technology, Inc > picosecond timing precision measurement > > jlarkin att highlandtechnology dott com > http://www.highlandtechnology.com
Reply by ●April 17, 20182018-04-17
On Tuesday, April 17, 2018 at 8:29:19 AM UTC-7, John Larkin wrote:> It would be fun to make a big CW, like a megavolt or something. A > string of cheap PC boards could do that.With air insulation, you'd find the limits at half a megavolt, if your room had a 12ft ceiling... When I say 'your' room, I don't intend that you should be in it when the power is on.
Reply by ●April 17, 20182018-04-17
On Tuesday, April 17, 2018 at 7:16:52 AM UTC-7, George Herold wrote:> On Tuesday, April 17, 2018 at 2:01:17 AM UTC-4, Jasen Betts wrote:> Thanks, I was looking through the DK site at transformers.... but I guess > that is not what I want... well there are some here, > https://www.digikey.com/products/en/transformers/switching-converter-smps-transformers/168.The usual reason for HV transformers (insulation and winding intended for the purpose) is to drive cold cathode fluorescent backlights (so, it's a source that's drying up). This datasheet says it all: <http://www.cooperindustries.com/content/dam/public/bussmann/Electronics/Resources/product-datasheets/BUS_Elx_PM_4303_CCFL_Transformers.pdf But, there's still a few lots on eBay, and a lot of elder displays that can be donors...
Reply by ●April 17, 20182018-04-17
On Tuesday, 17 April 2018 17:51:22 UTC+1, George Herold wrote:> I'm not sure what you mean by a string of PC boards. > I've got this guys book, where he makes a 250 kV C-W. > http://www.diyphysics.com/2012/02/09/d-i-y-250-kv-high-voltage-dc-power-supply-with-neat-trick-for-switching-polarity/#more-614 > > I think you need to start worrying about x-rays at those voltages. > > Oh, the UCSB fel runs off a huge Van de Graff. (I guess it's real name is > a pelletron.) > http://sbfel3.ucsb.edu/ > > George H.x-rays start a good order of magnitude below that NT
