Best 5V SMPS ?

[soundcheck]

Unfortunately there is no other than the Amplifier-Power Supply section at DIY-A.

I give it try over here with this topic.

***

I'm looking for a very good (DIY-) 5V SMPS ( and/or tweaks) out there. Yep - no linear supply!!!

Applications are endless for these.

RPI, HAT devices, routers, PC peripherals, you name it.

Right now I'm quite happy with the iFi iPower. With 2.5A it also delivery plenty of power.

iFi claims 1uV noise. Which obviously can be considered quite a low value. However. iFi excludes mains and switching related noise. Hmmh. And they limit it to the audio band. Hmmmmh I'd be interested to see what's left of that 1uV - if you take the exclusions out.

Anyhow. I still think and know from experience that the device performs really well.

I tried to put a Meanwell RS15-5 (@5.5V) + TPS7A4700 up against the iPower. That combo didn't perform on the same level.

Any ideas for approaching the subject are welcome. Maybe also ideas of how to get e.g. the Meanwell noise (80mV) down would be good starting point.

Cheers

BTW: I added some mods to the iPower. I shortened the cable down to around 12 inches and I also added a large buffer cap at the end of the cable.

[peufeu]

For stuff like a Pi or a router, power supply noise is irrelevant. If it has 5V input, internally it must run on 3V3 and other lower voltages, which means it has internal regulators, most likely switching.

What is relevant:

- If target device is connected to an audio system through cables, then common mode current generated by the power supply will flow into those cables and contaminate grounds. This really is the most important spec. It is really hard to get rid of common mode currents. Power supply design needs to take this into account right from the start.

- Radiated electromagnetic fields

- Amount of noise injected into the mains (and picked up by nearby equipment).

- Fire & electrocution hazard with "too cheap to be true" phone chargers...

[soundcheck]

Power supply noise is never irrelevant in the context of high quality audio power networks!!

[29285]

can you backup your general claim by some relevant content?

[soundcheck]

R u kidding me?

[bambadoo]

Just for reference and information. Archimago made some measurements with rpi3 using a couple of different PSUs.
Archimago's Musings: MEASUREMENTS: Raspberry Pi 3 as USB Audio Streamer (with recommended CRAAP config & TIDAL/MQA arrives)

But - good quality psu are never wrong.

Best regards.

[peufeu]

Originally Posted by soundcheck

R u kidding me?

Well, unless there is a big design mistake like :

- using the Pi as the DAC master clock
- using the same power supply both for the Pi and the DAC without appropriate care

Then yeah, it's pretty much irrelevant. Besides, if you measure the Pi's supplies while it works, or even the output of your "low noise" supply with the Pi connected and powered, I'm pretty sure you'd find the usual huge amount of noise associated with digital supplies. Go on, grab your scope probes and post a screenshot, it takes very little time...

> But - good quality psu are never wrong.

Sure!
Just don't believe that because it has "1µV noise" written on it, there won't be 100000 times more noise once you connect a load which draws wildly varying current...

[jean-paul]

Originally Posted by peufeu

Just don't believe that because it has "1µV noise" written on it, there won't be 100000 times more noise once you connect a load which draws wildly varying current...

It all adds up doesn't it ?

[cdsgames]

Practically , I think that first you need to chose the design of the smps. In my opinion , the best candidate for a 5v (audiophile) solution will be the quasi resonant fly back. You will have less EMIs then any other solution.

Of course then you need to solve the ripple/noise/impedance .

[drgnanam]

this may be a starting point
PMP8363 85VAC-265VAC Input, 5V@2A Eco-Charger Reference Design for Tablets and Smart Phones | TI.com