U-Amp wiring

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Hello everyone,

months ago i started my own PS2 Portable project and i finally have time to finish it.

The portable comes together well but i still need to figure out the sound.
I bought the U-Amp Board frome the BitBuilt Store but i need help with the wiring. I found the documentation here but I still have some questions.

I'm sure it's pretty straight forward but since I am a beginner in electronics i need to ask unfortunately...

First thing i need help about is the voltage. In the documentation it sais that IVDD for ps2 is 1.8v. But where do i get that from? According to the PS2 trimming guide there is 1.75v somewhere on the borad. So do just need to wire from there to the U-Amp board? Is 1.75v even enough? Or do i need a resistor on other voltage sources?
And what about the 3.3v supply voltage U-Amp needs?

My second question is about the digital sound.
The wiring here is pretty straight forward thanks to the awesome documentation. But do I still need to wire up the Analog Audio R and Audio L when i use the I2S interface?

I hope you guys can help me out. Thanks
 

cfc_12

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Yes, 1.75v is enough for 1.8v

Yes, 3.5v is fine for 3.3v

I believe, yes, you still need to wire the L & R for digital sound
 

Stitches

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You don't need analog LR for I2S audio, it's just there as an easier option for beginners
 
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Thanks for both the replies

You don't need analog LR for I2S audio, it's just there as an easier option for beginners
When I decide to use analog, I only need to wire LR, 3.3v and ground (and the switches for volume) is that right ?
Is there a disadvantage when I use analog instead of digital in this Szenario?
 

Stitches

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Correct, analog only needs 3.3v, and the "disadvantage" is a minor difference in sound quality
 
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Hey everyone.

I didn't want to open a new thread since i still have a problem with sound.

I decided to use analog audio for my Handeld but i cant get a single tone out of my speakers.
Maybe you can help figure it out if i show u what i used and how i wired everything.

The Speakers:
1619521657424.png

I don't know if these are simly wrong maybe?

The wiring:

Because i didn't trim the board that much i was able to get LR Audio from the Ps2 Composite Out pins on the board. I also took the 3.5v from the second memory card pin.
Messuring with my multimeter, Uamp does get about 3.4v so that seem to be correct i guess?
I soldered the red cable from the right speaker to the R+ pin on the uamp. And the black cable on R- (same for left speaker and L pins).

To rule out that the sound is just turned down, i also wired up the + and - microswitches but they dont seem to do anything.
At last i wired ground to one of the spots on the motherboard.

Is there something missing or wrong?
 
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So if you could can you post a photo of the connections from the audio amp on the PS2 and the wiring on the UAmp as well? No audio at all from analogue on the UAmp can be caused by a few things. The UAmp needs jumpers soldered, an input voltage on the ivdd pin and possibly the headphone sense pin connected to ground if you don't have a headphone jack wired. It's hard to say what's wrong without a wiring photo of what you did.

See the uamp doc and give it a further read,
UAmp Documentation
 
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Thank you so far. Here is how it looks
uamp wiring.jpg

The wires above lead to:
3_5volts_memcard.jpg

and
analogLR_ground.jpg

i did not make a photo of the speakers. I think the wiring there is pretty straight forward.

I hope this will help
 
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Might as well tie headphone sense pin to ground as well for the moment as you don't have a headphone jack connected, this will also help output to speakers. With what Ethan said above
Notes:

If headphones are not wired, then Headphone Sense (S) should be wired to ground to activate the speakers
 
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Oh i completely missed the analog config wiring in the documentation (because it was under the Dreamcast section. My bad)

I'll fix that and wire up like you guys suggested and let you know if it helped

Thank you
 
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