Yeap the new filter will have a "screw out" so you can have quite a small length cable (awg 16) going to audio device. Vin is by dc jack and usb (3A rated on all inputs and outputs)
But this new active filter is really something nice. -50db from 10Hz to 20Khz , add the inductor attenuation as well. Should make most (99%) smps quiet as a battery . (20uV)..at full 3A
But this new active filter is really something nice. -50db from 10Hz to 20Khz , add the inductor attenuation as well. Should make most (99%) smps quiet as a battery . (20uV)..at full 3A
Will be looking forward to that. In the meantime, to go back to Soundchecks original question. Soekris is using Mean Well supply in his dac.
http://www.soekris.dk/images/dac1541_open_1200.jpg
Any comments to his solution?
Does this give any ideas to how the Mean Well could be "tamed"?
http://www.soekris.dk/images/dac1541_open_1200.jpg
Any comments to his solution?
Does this give any ideas to how the Mean Well could be "tamed"?
We have been testing since Friday. Of course many problems...we got ripple of 1000mV
We have been testing since Friday. Of course many problems...we got ripple of 1000mV
1000mV = 1V out of 5V !?!?
Wow. You (or your supplier) managed to build the worst supply ever.
I was actually hoping to play around with one of your devices before Christmas.
Christmas 2017...
Let see how things are developing.
Once your're done with the finetuning and related measurements...
...don't forget to run listening tests!
While we're at it...
We already discussed that future Allo HATs should all have the same powering scheme (jacks and jumpers to disconnect power rails from lower and upper boards). Meaning. The user should be able to easily attach a single 5V supply to a complete tower or power a group of boards (e.g. Kali and DAC) or power each board separately.
Obviously the target behind it is primarily to achieve a little better performance and not boosting your product sales. (This would be a nice side-effect from your perspective though)
Enjoy.
...don't forget to run listening tests!
While we're at it...
We already discussed that future Allo HATs should all have the same powering scheme (jacks and jumpers to disconnect power rails from lower and upper boards). Meaning. The user should be able to easily attach a single 5V supply to a complete tower or power a group of boards (e.g. Kali and DAC) or power each board separately.
Obviously the target behind it is primarily to achieve a little better performance and not boosting your product sales. (This would be a nice side-effect from your perspective though
)Enjoy.
there are varous design choices related to the switching frequency vs the audio clock frequencies used in the system. one is to use a fixed dcdc frequency, like possible in the zvs resonant design, giving up some input range (although there are 3phasic options to combat that) and burn away some heat linearly to adapt to input voltage variations.
the fixed frequency can be set to lay either outside the audioband of interest, the harmonics will at some point conincide with clock harmonics. the next option is to sync the dcdc freq to a multiple of the audio word clock , for example 192kHz or 384khz .
the resonant designs have a considerably lower common mode noise due to weaker coupling between secondary and primary. and that is the noise that enters into the system, not the nosie across the terminal..
the fixed frequency can be set to lay either outside the audioband of interest, the harmonics will at some point conincide with clock harmonics. the next option is to sync the dcdc freq to a multiple of the audio word clock , for example 192kHz or 384khz .
the resonant designs have a considerably lower common mode noise due to weaker coupling between secondary and primary. and that is the noise that enters into the system, not the nosie across the terminal..
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