Help, power supply for tpa3251-4ch-100w 3e Audio

Jump to Latest
S

SmileX3

Member
Joined 2018
#1
Hi All, please help,

What would be a good power supply match that is readily available (in US) to buy for my 3e Audio TPA3251 4x100W 4Ch Class D Audio Amplifier board?

The Data sheet says: "Single supply voltage range 24V~36V(UVP:24V)" with note,
"*PVDD can higher to 36V but depend on full output power and thermal condition,30V is recommended in this design"

Web page:
TPA3251-4CH-100W | 3e Audio
data sheet:
http://www.3e-audio.com/wp-content/uploads/2018/07/DS_EAUMT-0100-4-A_Rev1.0.pdf

Thank you,
Steve
 
#3
The Meanwell LRS-350-36 would be a good choice. The datasheet says that the voltage can be adjusted down to about 32V, or possibly a bit lower.

I speculate the following basis for the the note from 3e-audio you mentioned:
PVDD can higher to 36V but depend on full output power and thermal condition,30V is recommended in this design
Click to expand...
This advice is probably related to thermal dissipation limitations of the heatsink on the amp board. To get 4 channels at the specified power requires TWO TPA3251, each in BTL mode. The amp board can theoretically drive four 4 Ohm loads, but this would probably be too much heat output if you run the amp using the maximum 36V supply. You could reduce the supply to 30V or so if you want to use 4 Ohm loads, or you can use 8 Ohms loads at 36V. Your choice.

In either case, the LRS-350 should be able to power the board just fine.
 
#4
Thank you drMordor and CharlieLaub for your helpful responses.


Another question, the Meanwell LSR-350-36, does this create "noise" or electrical noise problems for audio which I am trying to make sure is pure as possible for my project?


I bought 2 of these 4ch amps to try to use it as a surround sound solution. 7.1 But I was going to make them as two discrete electronic components both with 4ch and then use in parallel. This is my first audio project. I read that IEEE article on how to make your own d-class amp a while ago but only recently saw on ebay the components became available to buy. Anyway, any thoughts or comments to improve are welcome.

Thank you,
Steve
 
#6
I have the same board running with a cheap JCY-2460 24V 6A (ebay) laptop style power brick which stays cool an no noise.
The board runs 2x 4 Ohm mains and 2x 2 Ohm with a DVC sub fine where min 3 Ohm is specified.
As power supplies can often deliver 150% peak power, a PS 2/3 the size of the max clean output is fine to get all out of it.
Double power is only 3dB more output, so if you are not using these last 3 dB's or if you use 8Ohm speakers, you will be fine with an even smaller power supply.
 
Last edited:
#7
Thank you grahamgraham, I won't leave a ch without a load per your advice.


Thank you Think, interesting on the power supply option maybe I'll end up with something like that if the other supply kicks in the fan and creates horrible noise.
 
#10
Hey, JD2. I'm really not sure about the PSU but I can only warn about the amp. I didn't believe it was necessary to have all channels hooked up but having lost two TPA amps to this I wouldn't risk it going forward (other board members had warned me but I'm a learn-by-experience type of numpty).

I too have a 3E 4x100w amp sitting in its box along with the Mean Well LRS-350-36 to be used as my main bi-amp. I am sure it will be ample. It will be interesting to pitch it against my 4 channel class AB amps.

Daniboun, I hadn't noticed that PSU from Audiophonics, good shout.
 
#11
SmileX3 said:
Thank you drMordor and CharlieLaub for your helpful responses.
Another question, the Meanwell LSR-350-36, does this create "noise" or electrical noise problems for audio which I am trying to make sure is pure as possible for my project?
I bought 2 of these 4ch amps to try to use it as a surround sound solution. 7.1 But I was going to make them as two discrete electronic components both with 4ch and then use in parallel. This is my first audio project. I read that IEEE article on how to make your own d-class amp a while ago but only recently saw on ebay the components became available to buy. Anyway, any thoughts or comments to improve are welcome.
Thank you,
Steve
Click to expand...

Hello,
I've bought and tested the plate TPA3251 (EAUMT-0100-4-A) and its PSU (EAPST-0200-36-A).
This plate is noisier than a cheap TPA3116 ebay plate with the gain at 20dB when tested with a Linear PSU and the EAPST-0200-36-A is very noisy, the swithcing noise is very loud, the lowest range of my scope is 500µV therefore i can't give a measurement.
There is perhaps some people here that "don't hear anytning at all" but i was able to ear the noise from a closed adjacent room, this is perhaps beacause some testers are very old i don't know but this stuff is very noisy at idle.
 
#13
grahamgraham said:
............I didn't believe it was necessary to have all channels hooked up but having lost two TPA amps to this I wouldn't risk it going forward (other board members had warned me but I'm a learn-by-experience type of numpty).
............
Click to expand...
To bad this happened. Can you name the boards? Any 3e?
This phenomenon this is still a bit of a mystery to me and does not seem to happen with big brand class D amps.
 
#14
silverprout said:
Hello,
I've bought and tested the plate TPA3251 (EAUMT-0100-4-A) and its PSU (EAPST-0200-36-A).
This plate is noisier than a cheap TPA3116 ebay plate with the gain at 20dB when tested with a Linear PSU and the EAPST-0200-36-A is very noisy, the swithcing noise is very loud, the lowest range of my scope is 500µV therefore i can't give a measurement.
There is perhaps some people here that "don't hear anytning at all" but i was able to ear the noise from a closed adjacent room, this is perhaps beacause some testers are very old i don't know but this stuff is very noisy at idle.
Click to expand...

Anybody else have this experience with noise?
 
#15
silverprout said:
Hello,
I've bought and tested the plate TPA3251 (EAUMT-0100-4-A) and its PSU (EAPST-0200-36-A).
This plate is noisier than a cheap TPA3116 ebay plate with the gain at 20dB when tested with a Linear PSU and the EAPST-0200-36-A is very noisy, the swithcing noise is very loud, the lowest range of my scope is 500µV therefore i can't give a measurement.
There is perhaps some people here that "don't hear anytning at all" but i was able to ear the noise from a closed adjacent room, this is perhaps beacause some testers are very old i don't know but this stuff is very noisy at idle.
Click to expand...

I would also be interested in knowing if this is a problem, it's one out of 3 amplifiers I'm looking at. 🙂
 
#20
NVM post above.

Tried again this morning, and when I applied power I saw the red LED for 3.3V. I never saw this light up last night.

Then input some music, and now I get sound out of it.
I did disconnect and reconnect the input power connector, but had done that last night too and it made no difference.
My guess is somehow it reset it self over night and so now it works, but not really sure.

Randy
 
You must log in or register to reply here.
Top Bottom