New Fnirsi DPS-150 mini lab power supply (30 V, 5 A, USB PD powered)

[I wanted a rude username]

Anyone tried this yet? DPS-150, available from Fnirsi's store on AliExpress (currently on special for USD $55) but not listed on Fnirsi's site and I couldn't find any reviews of it yet.

Seems comparable to the DP100 but with a pop-up display that could be useful:

[DaneLaw]

Give it some weeks.
Fnirsi tends to lubricate most of YT's tech-influencers with Fnirsi's en'masse, so there will likely be dozen videos of DPS-150 in a few weeks, and hopefully at least one of them' takes it for a ride.
Fnirsi's product is a hit or miss, some of them are surprisingly decent with the price in mind, while others are dancing on a fine line of being close to defect.

Quite sparse with info on the promo-listings, its the same Fnirsi spec-limbo (low noise) without any tolerances... PD support, without any specs for what power delivery standard it carries.. One could hope with. its 150W rating, its PD3.1 from its TypeC as a lot of products & powerbanks are getting PD3.1 support (28v 5A) at significantly lower prices than previously, but the mixed barrel DC + Type makes it easy to use of-the-shelf PD3.1 triggers.

The manual
https://www.fnirsi.com/cdn/shop/files/DPS-150_Manual.pdf

[2vlado]

Those banana jacks don't appear to be 19mm apart

[DaneLaw]

Those banana jacks don't appear to be 19mm apart

They sadly ain't, I reckon the DP100 from Puntual Atomic (Alientek) is the standard dimensions, as Dave (EEVblog) seemed to use BNC adapters in his vid.

[jwr]

I just got one of these. I didn't expect much from it, but either I got a defective unit (no output cap?) or something is really wrong. The ON state is much more noisy than I expected (>750mV peak to peak at 5V!), but the OFF state… not everything will survive negative 6V.

Does anybody else see that?

[Aldo22]

It also depends on the source.
I see some noise too, but not as much as you do.

https://www.eevblog.com/forum/testgear/new-miniature-programmable-dc-power-supply-fnirsi-dps-150/msg5680887/#msg5680887

https://www.eevblog.com/forum/testgear/lab-power-supply-turn-on-and-off-characteristics/msg5680719/#msg5680719

[jwr]

Hmm, interesting… none of these other images show the behavior I'm seeing: negative voltage when the PSU is OFF. That's what I'm most concerned with, although a ripple of >750mV peak to peak at 5V output is pretty concerning, too. Perhaps I got a faulty unit after all?

(I tried with two different USB-PD power adapters, one from Anker and one from Ugreen, but that shouldn't matter — I might expect a little more HF noise with a crappy adapter, but not negative 6V)

[Aldo22]

Perhaps I got a faulty unit after all?

Possible. I have never seen these negative voltages on my device.

Please use the main DPS-150 thread for further posts, otherwise the information will become cluttered.
https://www.eevblog.com/forum/testgear/new-miniature-programmable-dc-power-supply-fnirsi-dps-150/

[TheDefpom]

I reviewed this unit a couple of months ago, in case it is of help.

[jwr]

Yes, I watched that video — the startup behavior and noise you were seeing are about what I would expect from this device. Your video doesn't show no-load behavior in the OFF state, but judging from the startup capture, you don't get negative voltages there.

My startup into with a 6k8 load connected looks like this:

[DaneLaw]

Hmm, interesting… none of these other images show the behavior I'm seeing: negative voltage when the PSU is OFF. That's what I'm most concerned with, although a ripple of >750mV peak to peak at 5V output is pretty concerning, too. Perhaps I got a faulty unit after all?

(I tried with two different USB-PD power adapters, one from Anker and one from Ugreen, but that shouldn't matter — I might expect a little more HF noise with a crappy adapter, but not negative 6V)

Try with a clean battery source.
just to rule out, your DC source, as some of these fast charge handshake protocols, can get a little confused, but it obviously shouldn't to the extent your witnessing.

[Aldo22]

Perhaps I got a faulty unit after all?

I tried it again with a 45W PD Charger.
I see the same thing as you with this one.



I probably hadn't noticed because it had a 50 Ohm load resistor.
The negative voltage disappears with the LR. It is about 0.13mA AC




Normally I use the linear power supply as the source for the DPS-150, when I work with the oscilloscope.
You don't see any major problems with this one either, just a small ripple that disappears after switching on.




I think your device is fine.