What about SSM3582?

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Where is the buzz about this chip? I find it super interesting!

Info from the spec sheet:
"Digital input stereo, high efficiency Class-D amplifier
Operates from a single 4.5 V to 16 V supply
State-of-the-art, proprietary, filterless Σ-Δ modulation
106.5 dB signal-to-noise ratio
0.004% total harmonic distortion plus noise (THD + N)
at 5 W into 8 Ω
38.5 μV rms A weighted output noise"

I am dreaming about a super easy, cheap, low noise, cool running amp with direct connection to dsp!

Can someone please make a great layout for this?

Edit:
Oh, and I just have to coin this phrase: 5 watts ought to be enough for anyone!
 

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Looks to me to be rather let down by having a DAC inside rather than a direct conversion from PCM to PWM as do many other chips (STA333 and LV4904 to name just two).

I can understand your point of view, but comparing noise floor between chips it seems to me that most very low noise class D use analog input, or just a dac like on this. Anyway, it seems relatively comparable to the LV4904V only the SSM3582 is lower noise?

Just look at the ICE modules, really low noise stuff, but with analog in. A lot of the PCM to PWM seem to hit some barrier at maybe 100db. And also the option to just connect the SSM3582 with i2s makes it pretty versatile.

I am rather interested in a sort of Pass ideology but with class D amps, "the first watt is the most important watt" or something like that. And in my opinion the most long term tolerable class D are often the lowest noise ones. To get more than 5 really low noise watts, and it's also stable at low z loads, SSM3582 looks like a price/performance champion to me.
 
I'm using 5 of these chained on TDM output from a DSP. Looking forward to bench testing!

3eaudio - they work in stand alone mode too!

Small mono mode board layout idea below. Don;y think it really needs the choke or output filter caps. Depends if your cables are 20cm+.
 

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I'm using 5 of these chained on TDM output from a DSP. Looking forward to bench testing!

3eaudio - they work in stand alone mode too!

Small mono mode board layout idea below. Don;y think it really needs the choke or output filter caps. Depends if your cables are 20cm+.

Interesting that you're going with 5x mono setup. Very nice low z capabilities in mono. Do you have any way to measure how it performs in your setup?

One thing I like about this: it's the perfect match for a 12v 7ah SLA with a cheap charger, makes a real easy setup.

Edit:
Nevermind
 
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Yes indeed. I'll be using an Audio Precision APx515 to test the board - traded up a Rohde UPV.

The plan was to use a 120W Vicor DC-DC (8-60v in, 16V out) buck-boost and a LT3042 for the 5VADD supply. However, looking at the specs the internal LDOs on the SM3582 seem very good already. I just liked the idea of keeping those suppliers away from the high transient main PVDD supply.

I plan to investigate:

- various bypass caps from X7R to Panasonic ECPU, Cornell FCA and Rubycon MU.
- THD effect of chokes such as the DLW5BTN for longer cable lengths.
 
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Yes indeed. I'll be using an Audio Precision APx515 to test the board - traded up a Rohde UPV.

The plan was to use a 120W Vicor DC-DC (8-60v in, 16V out) buck-boost and a LT3042 for the 5VADD supply. However, looking at the specs the internal LDOs on the SM3582 seem very good already. I just liked the idea of keeping those suppliers away from the high transient main PVDD supply.

I plan to investigate:

- various bypass caps from X7R to Panasonic ECPU, Cornell FCA and Rubycon MU.
- THD effect of chokes such as the DLW5BTN for longer cable lengths.

Very exciting!
I am a bit curious about whether it feeds any noise back to the power bus if you have several on the same psu. And if a few diodes and a nice little cap can be enough to separate this noise.
 
My initial plan for these amps was a 16-channel church organ project tethered from a LynxTwo TDM interface. Each channel was going to be two Common Sense Audio Super 8s, 10s and 12s with certain instrument groups directed to each speaker. The Super12 is something like 100db sensitivity so doesn't need much to go loud. The last thing I want is hiss in quiet passages. I have also investigated TDM over IP/PoE so that the amp boards could be 2 or three centimetres from the driver. The UniFi 24-port switch has a great 250W 24V/0.5A passive or 48V/0.5A supply. For the moment sticking to groups of 5, maybe 4 amps.
 
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I've tried to tell in a previous thread that I find the ssm-3582 pretty good but since there was no comments, I though nobody is interested in a 2x15W amp and I didn't bother.

Here's a video of my setup with 4 x SSM-3582 you might find interesting
https://www.youtube.com/watch?v=CbaCjv7SLhE

my 4 Tact 2150s will probably end up in the attics or ebay.

I've tried different class-D amps and I find that the ssm is low cost, tiny footprint, easy to build and really easy to operate.

If you want to give it a shot, attached herewith are my pcb layout files.
 

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The SSM3582 appears to be a variant of the excellent SSM3302. It's got the built-in DAC to provide the digital interface with auto-shutdown, but I assume the amplifier section is the same as the SSM3302. I believe the SSM3302 is a descendent of the ADI's AD1992-series of amps, which were described in several EE publications back in 2005. They are well engineered, with a far more sophisticated design than the previous generation of class d amps. Here is a link to one of those articles: Integrated Stereo Class D Amplifier_ͼÎÄ_°Ù¶ÈÎÄ¿â.

I've got a "line array amp" with 7 SSM3302 chips (one is a spare), along with 4 SSM2518 chips. They are feed by 3 ADAU1701 chips. The board "works" in that it powers up and the amps all have the right voltages, but I haven't written the code yet for the micro. I decided to hold off on the software until I got further along with the cabinet for all of the drivers. I did some work on the cabinet this past weekend, but still have a long way to go.

If I had to redesign this board, it would be with the ADAU1452 chips and the SSM3582. I would also use an Arduino ARM CPU--I'm tired of programming in assembly language.

line_array_amp_stuffed.jpg
 
...

If I had to redesign this board, it would be with the ADAU1452 chips and the SSM3582. I would also use an Arduino ARM CPU--I'm tired of programming in assembly language.
...

:-D
I noticed somewhere in the spec sheet that they suggest using muliple layer pcb's, specificly: one plane for digital power with one plane for digital ground underneath, and one plane for analog power with one plane for analog ground underneath. If you throw in some signals and stuff too then we're probably just as well off with a 6 layer ultra compact layout?

I really like your idea of putting ADAU1452 and maybe some Arduino stuff onboard, this is starting to sound like a 1 pcb ultra compact solution with direct usb connection for adjusting filter settings. A much more compact and end user friendly solution than the FreeDSP stuff probably.
 
I've tried to tell in a previous thread that I find the ssm-3582 pretty good but since there was no comments, I though nobody is interested in a 2x15W amp and I didn't bother.

Here's a video of my setup with 4 x SSM-3582 you might find interesting

...

If you do not mind me asking, what sensitivity are your speakers?
And the follow up question is: do you consider the SSM3582 to have enough headroom if you engage party mode after some wine, cognac and beer?
And in case of party mode: How does it perform under pressure?
Or are you using the built in limiter?

I am curious about the feel of the distortion, I can imagine that if listening to some dynamic tracks that you might get into high thd on peaks if using 90db/w or lower speakers.

Edit:
Maybe it would be best to mate the SSM3582 with the Insanity Freedsp kit, or maybe the piDSP would be a lighter option.

Edit2:
From the datasheet:
"Properly designed multilayer PCBs can reduce EMI emission
and increase immunity to the RF field by a factor of 10 or more,
compared with double-sided boards. A multilayer board allows
a complete layer to be used for the ground plane, whereas the
ground plane side of a double-sided board is often disrupted by
signal crossover.
If the system has separate analog and digital ground and power
planes, the analog ground plane must be directly beneath the
analog power plane, and, similarly, the digital ground plane must
be directly beneath the digital power plane. There must be no
overlap between the analog and digital ground planes or between
the analog and digital power planes. "
 
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Here's my version with 5 SSM3582 attached to TDM port - well under way.

8-60V input supply
D2Audio DAE-6 DSP
5 x SSM3582 in mono mode connected by TDM.
XLR input / THAT1280
2 x isolated SDPIF in (micro bnc)
1 x isolated SPDIF out (micro bnc)
1 x stereo headphone out (filtered PWM from dsp)
12 x PWM out header
1 x PIC32MX (with attempt at i2s transfer into DSP).
 

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... if you engage party mode after some wine, cognac and beer?... "

"wine, cognac and beer" way to go buddy!
I'd say there're tons of suitable amps out there. that is if the concern of yours is the ability to make lot of noise for a bunch of people heavily loaded with substances

Regarding volume level, my main concern has been low level for certain classical recordings and this is how I solved it (post of Dec 4, 2016):
https://parallella.org/forums/viewtopic.php?f=51&t=1752&start=70#p18353

promised I'll talk about the "bloody" thd after you have another glass of those...
 
"wine, cognac and beer" way to go buddy!
I'd say there're tons of suitable amps out there. that is if the concern of yours is the ability to make lot of noise for a bunch of people heavily loaded with substances

Regarding volume level, my main concern has been low level for certain classical recordings and this is how I solved it (post of Dec 4, 2016):
https://parallella.org/forums/viewtopic.php?f=51&t=1752&start=70#p18353

promised I'll talk about the "bloody" thd after you have another glass of those...


Most of my "party mode" listening is clean sober in broad daylight, as I have small kids, but I've always been like this since I got my first setup when I was 14. I like to play loud around 12:00 on sundays because there are so few other disturbances then, and if I'm lucky the kids are out playing with friends, and hopefully the missus can sit down and be quiet for a little while.

I think the SSM3582 will be more than sufficient to cover my need for volume under regular circumstances, it's the "really loud 12:00 on sunday" with very dynamic recordings I am concerned about. People make too much noise and talk too much to enjoy the music, so not really concerned about that, merely using it as an example. I hardly ever drink enough to get a slight buzz even, think i'm up to ca 1 pint of beer/week average, maybe 2 pints/week sometimes, other times 0.

Edit:
But I have much more Beer and wine than I can consume, I enjoy making my own. If you only drink 1 pint a week then better make sure it's a good one!
 
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