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  • cute little switcher

    From John Larkin@21:1/5 to All on Wed Sep 20 11:33:39 2023
    https://www.dropbox.com/scl/fo/cx2tgk4xexj134kck54js/h?rlkey=qrp95nd26g5zy2bjqce1k5pfa&dl=0

    Diodes Inc AP63300. This will switch +48 down to 5/12/24 or whatever.
    I tested it because sometimes synchronous switchers make horrendous
    noise spikes, but this looks pretty good. The trick seems to be to
    tweak the doping so the substrate diode isn't an SRD.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jan Panteltje@21:1/5 to jl@997PotHill.com on Thu Sep 21 05:14:10 2023
    On a sunny day (Wed, 20 Sep 2023 11:33:39 -0700) it happened John Larkin <jl@997PotHill.com> wrote in <64cmgitdu9m6hrobm7rqllkagba0cjkdnq@4ax.com>:

    https://www.dropbox.com/scl/fo/cx2tgk4xexj134kck54js/h?rlkey=qrp95nd26g5zy2bjqce1k5pfa&dl=0

    Diodes Inc AP63300. This will switch +48 down to 5/12/24 or whatever.
    I tested it because sometimes synchronous switchers make horrendous
    noise spikes, but this looks pretty good. The trick seems to be to
    tweak the doping so the substrate diode isn't an SRD.

    OK
    second harmonic 1 MHz in the medium wave radio band...

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From John Larkin@21:1/5 to All on Thu Sep 21 07:21:26 2023
    On Thu, 21 Sep 2023 05:14:10 GMT, Jan Panteltje <alien@comet.invalid>
    wrote:

    On a sunny day (Wed, 20 Sep 2023 11:33:39 -0700) it happened John Larkin ><jl@997PotHill.com> wrote in <64cmgitdu9m6hrobm7rqllkagba0cjkdnq@4ax.com>:

    https://www.dropbox.com/scl/fo/cx2tgk4xexj134kck54js/h?rlkey=qrp95nd26g5zy2bjqce1k5pfa&dl=0

    Diodes Inc AP63300. This will switch +48 down to 5/12/24 or whatever.
    I tested it because sometimes synchronous switchers make horrendous
    noise spikes, but this looks pretty good. The trick seems to be to
    tweak the doping so the substrate diode isn't an SRD.

    OK
    second harmonic 1 MHz in the medium wave radio band...

    Switchers do that. I like the old Simple Switchers that run at 50 KHz,
    but they need a catch diode and gigantic inductors and capacitors.

    One of our products just/finally passed the CE EMI tests, after 6
    expensive EMI lab visits. That has a front-end isolated switching
    supply running at 100 KHz. The failure was conducted EMI on the 24
    volt input, which makes no sense since that's deep inside a big
    system.

    Fortunately, our cusomer paid for the testing.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From John Miles, KE5FX@21:1/5 to John Larkin on Thu Sep 21 11:55:33 2023
    On Thursday, September 21, 2023 at 7:21:44 AM UTC-7, John Larkin wrote:
    second harmonic 1 MHz in the medium wave radio band...
    Switchers do that. I like the old Simple Switchers that run at 50 KHz,
    but they need a catch diode and gigantic inductors and capacitors.


    Looks like this one can run at any desired rate up to 2.5 MHz, similar to the LT parts. It does look like a good alternative.

    One of our products just/finally passed the CE EMI tests, after 6
    expensive EMI lab visits. That has a front-end isolated switching
    supply running at 100 KHz. The failure was conducted EMI on the 24
    volt input, which makes no sense since that's deep inside a big
    system.

    Ouch.

    I thought I was being clever by using an LT3086 as a preregulator
    just behind the power entry jack on one box, running with about 1V
    of dropout headroom. No problem passing FCC/CE. Sailed right through.
    But it was sure as hell a problem when LT decided to stop shipping
    LT3086IRs for a year or so. :(

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jan Panteltje@21:1/5 to jl@997arbor.com on Fri Sep 22 04:55:45 2023
    On a sunny day (Thu, 21 Sep 2023 07:21:26 -0700) it happened John Larkin <jl@997arbor.com> wrote in <qvjogilaue84p27va21p324m9kgnsm3p53@4ax.com>:

    On Thu, 21 Sep 2023 05:14:10 GMT, Jan Panteltje <alien@comet.invalid>
    wrote:

    On a sunny day (Wed, 20 Sep 2023 11:33:39 -0700) it happened John Larkin >><jl@997PotHill.com> wrote in <64cmgitdu9m6hrobm7rqllkagba0cjkdnq@4ax.com>:
    https://www.dropbox.com/scl/fo/cx2tgk4xexj134kck54js/h?rlkey=qrp95nd26g5zy2bjqce1k5pfa&dl=0

    Diodes Inc AP63300. This will switch +48 down to 5/12/24 or whatever.
    I tested it because sometimes synchronous switchers make horrendous
    noise spikes, but this looks pretty good. The trick seems to be to
    tweak the doping so the substrate diode isn't an SRD.

    OK
    second harmonic 1 MHz in the medium wave radio band...

    Switchers do that. I like the old Simple Switchers that run at 50 KHz,
    but they need a catch diode and gigantic inductors and capacitors.

    One of our products just/finally passed the CE EMI tests, after 6
    expensive EMI lab visits. That has a front-end isolated switching
    supply running at 100 KHz. The failure was conducted EMI on the 24
    volt input, which makes no sense since that's deep inside a big
    system.

    Fortunately, our cusomer paid for the testing.


    Yes it makes ense to filter all in and out going power line.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)