DSM03 Power Spec Verification

chysn · « **on:** September 05, 2016, 10:13:48 PM »

Hey!

ModularGrid lists the DSM03's power consumption at

150mA +12V
20mA -12V
150mA +5V

Is that for real? It seems like it could just be someone's guess based on the the DSM02.

Steven Morris · « **Reply #1 on:** September 06, 2016, 11:46:39 AM »

Quote from: chysn on September 05, 2016, 10:13:48 PM

Hey!

ModularGrid lists the DSM03's power consumption at

150mA +12V
20mA -12V
150mA +5V

Is that for real? It seems like it could just be someone's guess based on the the DSM02.

FWIW, I've heard that a lot of the figures on Modular Grid RE: Power Consumption are false/guesses.

extempo · « **Reply #2 on:** September 06, 2016, 11:58:52 AM »

We don't have the final specs on current draw just yet, but I'll post them here when we do.

chysn · « **Reply #3 on:** September 06, 2016, 12:12:07 PM »

Quote from: Steven Morris on September 06, 2016, 11:46:39 AM

FWIW, I've heard that a lot of the figures on Modular Grid RE: Power Consumption are false/guesses.

Yeah, this is part of an effort to get accurate numbers directly from manufacturers. I've outgrown my power supply and need to upgrade.

Quote from: extempo

We don't have the final specs on current draw just yet, but I'll post them here when we do.

Thanks!

extempo · « **Reply #4 on:** September 19, 2016, 05:46:31 PM »

DSM-03 Feeback Module Current Draw:

+5v = 200mA
+12v = 10mA
-12v = 20mA

chysn · « **Reply #5 on:** September 19, 2016, 07:00:41 PM »

That's two hundred on the 5V rail?

extempo · « **Reply #6 on:** September 20, 2016, 01:51:24 PM »

Quote from: chysn on September 19, 2016, 07:00:41 PM

That's two hundred on the 5V rail?

Yes, this is correct. There are two processors in there, a general purpose micro-controller and a DSP, which utilize the 5v supply.

chysn · « **Reply #7 on:** September 20, 2016, 02:10:29 PM »

OK, thanks for confirming. That's an awful lotta juice for a eurorack module!

Robot Heart · « **Reply #8 on:** September 20, 2016, 04:17:29 PM »

After noticing your post in the other thread and looking around a bit, it seems like there are a lot of Eurorack PSUs that have robust 5V rail specs. This 4ms PSU has 1.5A at 5V and this Malekko PSU has 1A at 5V. The Doepfer PSU3 has 2A or even 4A(!) at 5V if the fuse is replaced.

Those are just a few examples. Admittedly, before your comment I knew nothing about 5V rail current maximums for Eurorack, so thank you for the research topic. It does appear the uZeus has a relatively low 5V output compared to some other products on the market.

chysn · « **Reply #9 on:** September 20, 2016, 08:33:13 PM »

Yes, this is all true. However, you'll find that the uZeus has a really lopsided market share for this sort of thing; it's the fifth-most-popular module on ModularGrid, and the only power supply in the top 100 modules. It's ubiquitous, is what I'm saying. TipTop was pretty reassuring about the prospect of powering the DSM03, but that's only because I have the 3A upgraded power supply.

So it's slightly possible that I'm not the only one who will be worrying about the DSM03's deep thirst for 5V.

BobTheDog · « **Reply #10 on:** September 21, 2016, 12:02:34 AM »

The Doepfer PSU3 has only been available this year though, the previous power supplies didn't even have 5V and the doepfer 5V adapter that can be added to these is only 100ma.

DavidDever · « **Reply #11 on:** September 21, 2016, 09:38:47 AM »

The impression I get is that the +5 VDC rail is considered to be an extension of the previously analogue-only ±12 VDC Eurorack power rail standards, with a specific nod to juicing up microcontrollers, DSPs, etc. at +5 (or down-regulated to +3.3 or +1.8 ) VDC.

While it is possible to down-regulate the (analogue) +12 VDC rail to (digital) +5 VDC, there exists the likelihood that this might increase the noise across all modules within the rack, on the positive rail, depending on the analogue design competency of the module manufacturer.

Also, there are quite a few synthesizer switching power supplies that run off ±12 / +5 internally, almost to a convention, which could easily be re-purposed to drive a custom Eurorack chassis. If you needed one off the shelf with even more output, you can get 'em:

http://www.jameco.com/z/RT-125B-Mean-Well-AC-to-DC-Power-Supply-Triple-Output-5-Volt-12-Volt-12-Volt-15-Amp-6-Amp-1-Amp-132-Watt_323775.html

So if you're a purist, get thyself a decent supply with a robust +5 VDC rail, or alternately, refuse to buy anything that has a microcontroller or DSP in it–but I think it's probably too rich to think that you could have it both ways.

chysn · « **Reply #12 on:** September 21, 2016, 10:38:58 AM »

Quote from: DavidDever on September 21, 2016, 09:38:47 AM

While it is possible to down-regulate the (analogue) +12 VDC rail to (digital) +5 VDC, there exists the likelihood that this might increase the noise across all modules within the rack

...

I think it's probably too rich to think that you could have it both ways.

I'd say Mutable Instruments would beg to differ. But as Robert Heart observed, a more capable +5V is more the rule than the exception. My goals for power in the future will (1) free up the 4HP that the uZeus takes up, and (2) replace the flying busboards with solid busboards.

extempo · « **Reply #13 on:** September 21, 2016, 11:10:01 AM »

Also, please note that, as with our Character module, the Feedback module has a jumper for Local or System +5v. When set to System, the module will draw 200mA from the +5v rail that your Eurorack power supply provides (if it indeed provides +5v). When set to Local, the power necessary to run the processors is derived from the +12v rail that your Eurorack power supply provides.

I doubled checked with our hardware engineer, who confirmed that the Feedback module is designed to where, when the jumper is set to Local, the draw on the +12v supply will be 210mA.

BobTheDog · « **Reply #14 on:** September 21, 2016, 11:40:42 AM »

Much better

chysn · « **Reply #15 on:** September 21, 2016, 12:13:50 PM »

Ha! There's no problem at all, then.

DavidDever · « **Reply #16 on:** September 21, 2016, 01:38:18 PM »

Quote from: extempo on September 21, 2016, 11:10:01 AM

Also, please note that, as with our Character module, the Feedback module has a jumper for Local or System +5v. When set to System, the module will draw 200mA from the +5v rail that your Eurorack power supply provides (if it indeed provides +5v). When set to Local, the power necessary to run the processors is derived from the +12v rail that your Eurorack power supply provides.

I doubled checked with our hardware engineer, who confirmed that the Feedback module is designed to where, when the jumper is set to Local, the draw on the +12v supply will be 210mA.

Nice! This is common sense at its best.

chysn · « **Reply #17 on:** October 13, 2016, 05:43:03 PM »

The new web DMS03 product page at https://www.davesmithinstruments.com/product/dsm03-feedback-module/ indicates

Current Draw: +12V = 10mA, -12V = 20mA

Nothing about the +5V rail there.

Robot Heart · « **Reply #18 on:** October 13, 2016, 05:55:58 PM »

It was an unintentional omission, it'll be updated shortly!

kisielk · « **Reply #19 on:** October 13, 2016, 06:14:59 PM »

Quote from: DavidDever on September 21, 2016, 09:38:47 AM

The impression I get is that the +5 VDC rail is considered to be an extension of the previously analogue-only ±12 VDC Eurorack power rail standards, with a specific nod to juicing up microcontrollers, DSPs, etc. at +5 (or down-regulated to +3.3 or +1.8 ) VDC.

+5V power rail was there from the beginning of the Doepfer A100 16-pin electrical specification, it's not an extension...

However it is true that modules these days use a lot more from 5V than they used to. A lot of modules also use 3V since most modern microcontrollers operate at that voltage, so it's hard to avoid having an onboard regulator anyway.

Now if only Doepfer had included a dedicated digital ground :/