So, am I wrong with this heavy psu 1200 w? Will ask seller how to regulate current, I was informed it can be designed to be a charger for big cars accumulators for cars, there is some current regulator inside. Will open psu to enable see what is inside and then will decide how to manage current isdues. For now I do not see significant difference feeding tpa3255 via psu 50v/1200w and HP adaptor 19,8v/90 W but there should be...
In general, most of the these commodity AC->DC supplies will "fold back" (reduce) the output voltage until they can satisfy the current required. So, if you have a 50V/10A supply, and you connect to a 1 ohm load, the output of the supply will reduce to 10V @ 10A. And it will do that for a long time until it decides there's a fault or something gets too hot. And then it might go into a skipping mode. But usually they can do it for a long, long time.
This is desirable because it means you can charge large capacitances on equipment (like the TPA3255 EVM) safely.
if you add a bunch of caps to the ouput of your power supply, turn on the supply, and then connect the TPA3255 EVM, you will see sparks and nearly 1000A flow as the charge in the PS caps you added gets dumped into the caps on the EVM. That is very bad, and stresses everything.
So, determine the current you need, and buy a supply that can deliver that current all the time with a bit of margin to account for crest factor. For example, if you have a 50V system and you want to deliver 300W into 4 ohms, that would be a 35Vrms sine (approaching 50V peak). And the current would be 9A rms. The tips of the sine wave would need 1.41 * 9 = 12A. And then you have efficiency to consider.
If you try to solve the peak demands with caps, then what works for 1 KHz won't work for 20 Hz. It's a bad way to go. Supplies are cheap. A 50V 20A supply should have ample margin and keep the TPA3255 really happy if you want to get the rated power from the product.
Remember, caps are designed to act as reservoirs for microseconds, not milliseconds, especially on class D amps
Also, the TPA3255 doesn't care much about supply noise. it's really robust in the that regard. See >>>here <<< for noise measurements on a cheap ACDC supply and the TPA3255 EVM.
-Matt
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Hi Everyone
I have a question that may have been answered before (apologies if true), on the original BOM from TI there are a bunch of components with 0 qtys. which is confusing to me. Is that a revision or design evolution kinda a thing?
Also for Muti channel amp (6boards/ 12 channels) using TPA3255EVM or 3eaudio boards, what is the most economical PSU solution? I'm considering this oneSMPS2000R +-92 230V Power supply (SMPS2000RxE v2) will this work or I have to have dedicated SMPS for each board?
I have a question that may have been answered before (apologies if true), on the original BOM from TI there are a bunch of components with 0 qtys. which is confusing to me. Is that a revision or design evolution kinda a thing?
Also for Muti channel amp (6boards/ 12 channels) using TPA3255EVM or 3eaudio boards, what is the most economical PSU solution? I'm considering this oneSMPS2000R +-92 230V Power supply (SMPS2000RxE v2) will this work or I have to have dedicated SMPS for each board?
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There are reserved pads on EVM board for mod, such as PFFB or other customizing. 0 quantities are those excluded components in default circuit.
@smps
this smsp is a dual power supply...for the Class D bard TPA3255 you neet "just" a good smps with single voltage.
my proposal is too look at the constant current what the psu is able to do continuously.
chris
What capacitors do you reccomend for output stage? I have bought 3eaudio board recently and I am a bit worried about condition of the used capacitors (see picture). As I'd like to change them for peace of mind, what kind of decent cap to use? Should it be low ESR, some audio dedicated one?
Panasonic FC, FM, Nichicon FG, KZ?
Panasonic FC, FM, Nichicon FG, KZ?
Attachments
Is that a “new” amplifier from 3eaudio? If it is, that’s unfortunate that the output filter caps appear like that. I would demand a full refund or a replacement if your amp is “new.”
The Texas Instruments TPA3255EVM amp uses Panasonic FC 1,500uF/63V Aluminum electrolytic capacitors in those positions. The Nichicon FG and KZ caps should be fine to use as well as long as they fit. With the TI TPA3255EVM amp, those caps are only used in the single-ended output configuration.
The 4 biggest ones are power filter caps, the grey blocks are the output filter caps.
Clean it first, it does not look defective to me, more like some spilled lunch...
Measure them if you can. If you can't just power up and keep an eye on it.
You can always replace it later, no extra damage if it fails.
it is the wave-soldering flux.
never mind.
there are many caps like 1000uF/1500uF/2200uF/63V can be replace since the size same or closed,it up to you,diy stuff things.
have fun on that.
Sir, Why 1800µ/63V? will single 4700µ/63V do?. I have a few good Elna 4700µ/63V lying around.
Thankyou
I just found a better version of the AIYIMA TPA3255.
AIYIMA TPA3255 Bluetooth 5.0 Sound Amplifier Audio AMP 325W*2 Stereo Class D Amplificador Power Amplifiers DAC PCM5102 Decoder
It has PCM5102 and QCC3003 and look like to have better cap.
But no changed supply rail caps. But must be better for modding. I hope
I plan to buy this. will it work with 48v powersupply or do i need to change regulator or use 36v powersupply?
Seriously? Why it is only on one capacitor then? (Beside the fact, it's on the top, where no soldering is done)
Dear mates, I have checked the heatsink and found it is getting hot even with no too much load. There is a thermopaste between chip and sink. Approx 45/50 degree. What can be a reason? I drive double chip tpa3116 board for low& tpa3255 for mid and high biamping , but tpa3116 is room temperature and tpa3255 is hot. And as I mentioned befire tpa3255 much less loudness against tpa3116, can be a heat the sign of improper operation?
Did you find an answer to this Q yet ?
First thing I would check are the input capacitors, depending on the chip's gain setting they need to be adjusted accordingly to match the change in input impedance.
For the tpa3116 see page 16 of the datasheet, the 3255 seems to have a fixed impedance of 20K according to page 7. What's the value of the input caps on the 3255 ? with 20K it should be 4.7u or more. Page 22 mentions 10uf caps ... anything lower would result in a high pass filter - hence the decline in bass response.
Furthermore the 3255 gain appears to be a fixed 21.5 dB (datasheet, page 7) whereas a 3116 is programmable between 20 and 36dB (page 14). If the two are set to different gains then that's where your difference in loudness is coming from.
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which is the current best finished in box or board tpa3255 2.0 product?
i got e3audio boards from the group buy but seeing somebody else's bad cap(?) on one of there boards is concerning. i felt the caps where cheaper than the original boards... i need to get one of my original e3audio boards out and compare to the new group buy boards.... hmm
anyway what about the finished in nice box amps or boards for 2.0 , not 2.1. dont care about bluetooth so much, if it does have bt. it needs to be low noise! I was under the impression the 2.0 boards where not that good. ie could not be run near full power due to pre-amp dc-dc converters being run very near max voltage or some concern like that... :/
the finished YJ 2.1 is good but a not able to get full power out, right? i remember looking at specs and seeing output power was lower than 2.0 tpa3255 amps.
this new one sold by Aiyima, people have linked to, is it anygood? not so sure from what i read on this forum thread....
AIYIMA TPA3255 Bluetooth 5.0 Sound Amplifier Audio AMP 325W*2 Stereo Class D Amplificador Power Amplifiers DAC PCM5102 Decoder-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group
I don’t like the lack of input switch.
I got the e3audio boards cus i thought they best but i also wonder what other options there are.... and future options as e3audio dont make amp boards anymore.
i got e3audio boards from the group buy but seeing somebody else's bad cap(?) on one of there boards is concerning. i felt the caps where cheaper than the original boards... i need to get one of my original e3audio boards out and compare to the new group buy boards.... hmm
anyway what about the finished in nice box amps or boards for 2.0 , not 2.1. dont care about bluetooth so much, if it does have bt. it needs to be low noise! I was under the impression the 2.0 boards where not that good. ie could not be run near full power due to pre-amp dc-dc converters being run very near max voltage or some concern like that... :/
the finished YJ 2.1 is good but a not able to get full power out, right? i remember looking at specs and seeing output power was lower than 2.0 tpa3255 amps.
this new one sold by Aiyima, people have linked to, is it anygood? not so sure from what i read on this forum thread....
AIYIMA TPA3255 Bluetooth 5.0 Sound Amplifier Audio AMP 325W*2 Stereo Class D Amplificador Power Amplifiers DAC PCM5102 Decoder-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group
I don’t like the lack of input switch.
I got the e3audio boards cus i thought they best
but i also wonder what other options there are.... and future options as e3audio dont make amp boards anymore.
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