TPA3255 - all about DIY, Discussion, Design etc

Hi,
I look for information, how much impact have PVDD (Supply voltage) to THD. I searched it in TPA3255 datasheet, but here are only graphs supply voltage to power output. First graph is on THD+N 10% and second on THD+N 1%.

I need know, can I use 36V power supply for TI TPA3255EVM board without impact to THD.

Thanks
 
Power supply help

Sorry if this is a noob question, but I'm trying to wrap my head around power supplies that have a "+/-" sign vs those that don't. If a power supply is rated as "+/- 48v" does that mean it has a center tap as well? ie, it has 3 terminals with +48v, 0v and -48v respectively? Is this what the EVM needs, or do I need one of those which only have 2 terminals, labelled "+" and "-"?
 
That listing looks entirely like split rails and you don't really want to waste half of the capability of the PSU by leaving the negative rail floating along. If you look at the data sheets for the most common PSU (I think it's the most common?), you'll see most of us are using +0/+48 SMPS, e.g. the Meanwell LRS 350-48, although a few are using the Meanwell SE 600-48 to power two modules.
 
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TPA3255 New build with enclosure

First post, enjoyed all the info even though most is over my pay grade.

I want to build a 3255 in an enclosed case.
Regarding the power supply, I would like it enclosed in the case in a small form factor.
Here is the link to the PS I am considering ( 800W DC48V LLC Switching power supply board for amplifier PSU TPA3255 amp etc | eBay)
In addition I want to add a power switch and volume control as well has the usual input and output jacks.

Do you folks know of a how to guide (website) for a rookie such as me?
My ignorance is in the volume control and power led wiring so far.

Thank you for your help in advance.
 
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:cop: Considering you gave no indication as to what research you have done, and r_kallar_2 provided some links to potentially helpful threads, I think you will not last long here if you don't adjust your attitude.

You could have simply said, "Thanks I've read those threads, I was looking for something more specifically to do with X Y Z..". I suggest you read the rules as well. diyAudio Rules paying particular attention to rule 11 regarding moderator directives before posting again.
 
Meanwell UHP 200W SMPS with TPA3255

I'm thinking of pairing the TPA3255 with this fanless 200W meanwell power supply (48V). [POWERNEX] MEAN WELL NEW UHP-200 200W Slim PFC Switching Enclosed Power Supply | eBay

Other than not being able to get the full power from the TPA3255 are there any other consequences?

The speakers it will be powering are the LXmini. Initially I want to use the 4xSE output and eventually get a second TPA3255 and use it in 2.1 mode to allow the powering of the Davey sub.

Thanks,
JD
 
I'm thinking of pairing the TPA3255 with this fanless 200W meanwell power supply (48V). [POWERNEX] MEAN WELL NEW UHP-200 200W Slim PFC Switching Enclosed Power Supply | eBay

Other than not being able to get the full power from the TPA3255 are there any other consequences?

The speakers it will be powering are the LXmini. Initially I want to use the 4xSE output and eventually get a second TPA3255 and use it in 2.1 mode to allow the powering of the Davey sub.

Thanks,
JD

Love my LXminis :).

A couple things. That power supply is rated at only 4.2 amps. 48 volts se output gives you a max of 17 volts rms to each driver, which equates to 36 watts and a little over 2 amps. Even if you are happy with 36 watts, you may run out of current.

If you are considering the EVM, the jumpers that need to be removed are actually surface mount soldered jumpers. Can't just remove and replace easily.

Mike
 
Having build and modded quite a few TPA3116 amps the 3255 looked really interesting. So ordered one (I went for the 3e-Audio one, looks a better build/layout/components) which arrived yesterday and sounding pretty good on initial listening, more critical listening after some run-time.

I find the heatsink runs some 8-10C hotter than ambient and the inductors 10-15C hotter, just wanted to ask if thats normal, especially the inductors. Possibly a bit hotter playing music rather than idling but not much in it. Its not greatly alarming but the 3116 runs a lot cooler, barely needs a heatsink.
Power supply is a 300watt 44vdc analog supply. A little unusual (most will be using a switch-mode supply I imagine) but I had all the PSU components to hand so that kept costs down,

Am also wondering about possible mods to the 3e-Audio board. Inductors look to be reasonable quality and replacing with large CoilCraft etc. would be very messy. I note the LC filter inductor is 10uh and cap 1uf, clearly tuned to a 4ohm load so will likely change the cap to .33uf for my 8ohm speakers. I would change the inductor to 15 or 22uh but not sure of the real benefit to SQ.

Cheers
 
Love my LXminis :).

A couple things. That power supply is rated at only 4.2 amps. 48 volts se output gives you a max of 17 volts rms to each driver, which equates to 36 watts and a little over 2 amps. Even if you are happy with 36 watts, you may run out of current.

If you are considering the EVM, the jumpers that need to be removed are actually surface mount soldered jumpers. Can't just remove and replace easily.

Mike

Output is pushpull, so it can generate +48 and -48V across speaker from single 48V supply...which is 34Vrms. Into 8 ohms that's 144W, and if the supply can do 200W and the system is 75% efficient, then it works handily for the peaks...
 
Am also wondering about possible mods to the 3e-Audio board.

When I eventually get mine I'll initially be looking at the power supplies to the TL072s to check that the switching reg isn't putting HF on their rails. Then I'll examine the kinds of loads these opamps are being asked to drive (TL07x doesn't have much drive capability if good SQ is desired) and lighten them if possible. Thirdly I'll look into transformer isolation of the inputs.

Output inductors I'll address later as in my experience they make a relatively small difference to SQ. However there is a certain satisfaction in getting the inductors to run cooler by seeking out lower loss types.