On Mon, 27 Nov 2023 03:29:31 GMT, Jan Panteltje <alien@comet.invalid> wrote:>On a sunny day (Sun, 26 Nov 2023 11:24:14 -0800) it happened John Larkin ><jl@997PotHill.com> wrote in <tc67mipuqp22ja3o24pu3n5k01ofmavihb@4ax.com>: > >>On Sun, 26 Nov 2023 16:34:15 GMT, Jan Panteltje <alien@comet.invalid> >>wrote: >> >>>On a sunny day (Sun, 26 Nov 2023 07:17:39 -0800) it happened John Larkin >>><jl@997PotHill.com> wrote in <odn6mi1b6p99mpku923anu2l7clbh7ejpo@4ax.com>: >>> >>>>https://www.dropbox.com/scl/fi/lujsxfrwlaiocsa2y7k60/P942_DC-DC_12.jpg?rlkey=jslmsa1si2kwbk3l00wph9dhe&raw=1 >>>> >>>>My PCB guy is overloaded, so I've taken over my board layout, which is >>>>another 3-phase alternator simulator. I enjoy doing a PCB layout now >>>>and then. >>>> >>>>Anyway, that's a floating power supply, +48 to isolated +-60 at about >>>>200 watts. What's scary is that those purple logic traces on layer 6 >>>>transition from ground referenced (left of the Coilraft planar >>>>transformer) to referenced to N, the isolated common and 3-phase >>>>neutral, layer 5 split plane. >>>> >>>>I love these things: >>>> >>>>https://www.dropbox.com/s/3d093msdmuinhxs/Coilcraft_PL300.jpg?raw=1 >>>> >>>>Coilcraft does great stuff. >>> >>>When I need a transformer I just wind one... >>> https://panteltje.nl/pub/ultrasonic_antifouling_bigger_transformer_IMG_5179.JPG >>>the math is simple >>> https://panteltje.nl/pub/ultrasonic_anti_fouling_circuit_diagram_IMG_5144.JPG >>> https://panteltje.nl/pub/home_made_1_to_33_hv_transformer_img_3096.jpg >> >>The math of ordering a standard part is simpler. And the parts cost >>about 1/20 as much. >> >>I only design what I can't buy. Weird stuff. I've never seen a >>transmission-line transformer for sale, or maybe inside a big metal >>box. >> >>Incidentally, Coilcraft does custom versions of that planar >>transformer. >> >>For modest numbers of turns, you can make the windings on your PC >>board and optionally snap a ferrite core onto both sides of the board. >>Still a hassle. >> >>I was wondering about using two halves of a pot core, bolted on to the >>board, with the FR4 making a rather large air gap. > >That would also break the outside magnetic coupling, >so basically get you very little core effect. >Normally in a potcore with airgap only the inner part is shorter, touches less. >? >Potcores are nice. > https://panteltje.nl/pub/8052AH_BASIC_computer/8052AH_BASIC_computer_inside_img_1727.jpg > eighties... EPROM programming voltage generator... > https://panteltje.nl/pub/8052AH_BASIC_computer/dc_dc_converter_detail/5V_to_30V_converter.jpg >almost a sinewave, no switcher noise...That last one has a base bias scheme that is more subtle than it looks. I did the same thing, but with the feedback winding in the emitter, for a gadget used on the C5A transport.
isolated +-60 supply
Started by ●November 26, 2023
Reply by ●November 27, 20232023-11-27
Reply by ●November 27, 20232023-11-27
On a sunny day (Sun, 26 Nov 2023 22:19:15 -0800) it happened John Larkin <jl@997PotHill.com> wrote in <p2d8mi93k4pcuvi6rqatb97a3j0r9vpss7@4ax.com>:>On Mon, 27 Nov 2023 03:29:31 GMT, Jan Panteltje <alien@comet.invalid> >wrote: > >>On a sunny day (Sun, 26 Nov 2023 11:24:14 -0800) it happened John Larkin >><jl@997PotHill.com> wrote in <tc67mipuqp22ja3o24pu3n5k01ofmavihb@4ax.com>: >> >>>On Sun, 26 Nov 2023 16:34:15 GMT, Jan Panteltje <alien@comet.invalid> >>>wrote: >>> >>>>On a sunny day (Sun, 26 Nov 2023 07:17:39 -0800) it happened John Larkin >>>><jl@997PotHill.com> wrote in <odn6mi1b6p99mpku923anu2l7clbh7ejpo@4ax.com>: >>>> >>>>>https://www.dropbox.com/scl/fi/lujsxfrwlaiocsa2y7k60/P942_DC-DC_12.jpg?rlkey=jslmsa1si2kwbk3l00wph9dhe&raw=1 >>>>> >>>>>My PCB guy is overloaded, so I've taken over my board layout, which is >>>>>another 3-phase alternator simulator. I enjoy doing a PCB layout now >>>>>and then. >>>>> >>>>>Anyway, that's a floating power supply, +48 to isolated +-60 at about >>>>>200 watts. What's scary is that those purple logic traces on layer 6 >>>>>transition from ground referenced (left of the Coilraft planar >>>>>transformer) to referenced to N, the isolated common and 3-phase >>>>>neutral, layer 5 split plane. >>>>> >>>>>I love these things: >>>>> >>>>>https://www.dropbox.com/s/3d093msdmuinhxs/Coilcraft_PL300.jpg?raw=1 >>>>> >>>>>Coilcraft does great stuff. >>>> >>>>When I need a transformer I just wind one... >>>> https://panteltje.nl/pub/ultrasonic_antifouling_bigger_transformer_IMG_5179.JPG >>>>the math is simple >>>> https://panteltje.nl/pub/ultrasonic_anti_fouling_circuit_diagram_IMG_5144.JPG >>>> https://panteltje.nl/pub/home_made_1_to_33_hv_transformer_img_3096.jpg >>> >>>The math of ordering a standard part is simpler. And the parts cost >>>about 1/20 as much. >>> >>>I only design what I can't buy. Weird stuff. I've never seen a >>>transmission-line transformer for sale, or maybe inside a big metal >>>box. >>> >>>Incidentally, Coilcraft does custom versions of that planar >>>transformer. >>> >>>For modest numbers of turns, you can make the windings on your PC >>>board and optionally snap a ferrite core onto both sides of the board. >>>Still a hassle. >>> >>>I was wondering about using two halves of a pot core, bolted on to the >>>board, with the FR4 making a rather large air gap. >> >>That would also break the outside magnetic coupling, >>so basically get you very little core effect. >>Normally in a potcore with airgap only the inner part is shorter, touches less. >>? >>Potcores are nice. >> https://panteltje.nl/pub/8052AH_BASIC_computer/8052AH_BASIC_computer_inside_img_1727.jpg >> eighties... EPROM programming voltage generator... >> https://panteltje.nl/pub/8052AH_BASIC_computer/dc_dc_converter_detail/5V_to_30V_converter.jpg >>almost a sinewave, no switcher noise... > >That last one has a base bias scheme that is more subtle than it >looks.Yes, auto-bias!>I did the same thing, but with the feedback winding in the emitter, >for a gadget used on the C5A transport.I have used that circuit with base feedback many many times, even to power an industrial optical link module once. That old thing from the eighties still works (tested last year)! Was part of my home control system... programmed in 8052AH BASIC.
