Hi
I am in the process of making my own amplifier. I have some projects where i need a decent mono chip and a bluetooth receiver for diy speakers. I wanted to make something, where i had to do some calculations my self, and found myself what i think is a good guide.
I really want to implement a 5v 1a dc outlet on the pcb for easy hookup of an Arylic up2stream mini receiver. Is this something possible, without getting ground looping etc?
Also for convenience sake, I'm buying a 29,2v dc power supply.
- The schematic from his site, some of my values are slightly different
I am in the process of making my own amplifier. I have some projects where i need a decent mono chip and a bluetooth receiver for diy speakers. I wanted to make something, where i had to do some calculations my self, and found myself what i think is a good guide.
I really want to implement a 5v 1a dc outlet on the pcb for easy hookup of an Arylic up2stream mini receiver. Is this something possible, without getting ground looping etc?
Also for convenience sake, I'm buying a 29,2v dc power supply.
- The schematic from his site, some of my values are slightly different
The circuit you show is a conventional chip amp that runs on a split rail supply... I assume that is what you mean with 29,2. You need a -29-0 +29 supply.
Adding a 5 volt regulator is easy but 5 volts at 1 amp (do you really really need 1 amp load current capability) means a linear regulator will generate a lot of heat... 29 volts less 5 volts which is 24 multiplied by 1 which is 24 watts. Hot, very very hot. That assumes you wanted to run the 5 volt reg from the main amp.
There are no grounding issues beyond returning the regulator grounds and the 5 volt load ground back to the power supply ground point. If you use a separate 5 volt supply the same applies for grounding.
This is more Chip Amp than Class D at this point. I'll move it.
Adding a 5 volt regulator is easy but 5 volts at 1 amp (do you really really need 1 amp load current capability) means a linear regulator will generate a lot of heat... 29 volts less 5 volts which is 24 multiplied by 1 which is 24 watts. Hot, very very hot. That assumes you wanted to run the 5 volt reg from the main amp.
There are no grounding issues beyond returning the regulator grounds and the 5 volt load ground back to the power supply ground point. If you use a separate 5 volt supply the same applies for grounding.
This is more Chip Amp than Class D at this point. I'll move it.
#2 Thanks. Whether it needs the 1a i honestly dont know.. All i Can see is that the arylic wants a 5v 1a power input. The board has a wifi and Bluetooth chip, But not much Else, that Im going to use.
When it is a split rail supply as you say.. is there any reason for it to not work with, for an example, laptop charger?
When it is a split rail supply as you say.. is there any reason for it to not work with, for an example, laptop charger?
The amplifier chip requires both a positive voltage above ground, and an equally negative voltage below ground, which is what is meant by +29V and -29V.
A laptop charger will only provide a positive voltage and ground, not the negative voltage. It is very difficult to find a modular power supply with both a positive and negative voltage, so you typically have to design your own power supply, along these lines:
https://www.ti.com/lit/an/snaa057c/snaa057c.pdf
A laptop charger will only provide a positive voltage and ground, not the negative voltage. It is very difficult to find a modular power supply with both a positive and negative voltage, so you typically have to design your own power supply, along these lines:
https://www.ti.com/lit/an/snaa057c/snaa057c.pdf
Many USB powered devices SAY they need 1A or 2A, etc, because those are common switching supply modules available for cell phone charging. What the device actually draws may be lower, or may be that high. I would probably build in a switching DC to DC supply module to directly convert the high voltage positive supply for the amp down to 5V- by being a switching supply rather than a linear regulator it will not have the overheating problem. Work out the supply issue for the amplifier first, then you can find a 5V switching supply module.
I see. That May be above what i can do in the moment. Im am afterall just a beginner, maybe i should find some other design then.
But i think you are right. I Will either find a Way to get a small power supply or find a new design. Then worry about the other stuff after.
But i think you are right. I Will either find a Way to get a small power supply or find a new design. Then worry about the other stuff after.
Laptop supplies tend to set limits on voltages available but have the advantage of being small and lightweight and probably cost effective as well. Having said that, is there any reason you wouldn't want to use just use a regular transformer + diode bridge + reservoir caps to generate a split supply?
Go for Class D amps, use laptop brick adaptor and then slowly progress towards Class AB amp with split supply.
Any mistakes in split supply connections and your speakers may get damaged
Okay, ill try to elaborate.
I have a pair of nice speakers for listening to serious music. When I don’t do that, my cousin and I build speakers for different use. The uses can be compared to sonos speakers and/or party speakers. Usually we just use an acrylic up2stream, but I would love to build my own amps, that maybe is slightly better sound quality (for the nice speaker drivers, and not too expensive). These builds are often mono speakers at around 10 liters or more. So ideally in the future, I want to build some pcb that can deliver some watts, can be driven by batteries (or laptop charger), and then connected with a 5v Bluetooth board.
What I liked about the amp I showed was basically that there was a guide, where I got to do the calculations. I just want to learn, and feel like I give it my own spin.
If anybody has any nice threads on here, feel free to send them to me..
I was looking at building an amp with the 3255, but I don’t know how clean the mono is in that one.
Thank you all for writing.
Might just do that. I just liked the idea of a clean build (it’s going to be inside a speaker, so fewer wires are better)
The first thing to do is write down your own specification for what you want rather than just picking designs you think might work. In particular you need to know your power supply options... what have you got available. In other words if you want an amp to run off batteries as well (and that is a major factor) you need to begin by stating what the battery size (its capacity) and voltage is.
If you only have a 12v SLA (gel batteries like in alarm panels) as a battery for example then that limits your options massively.
A TPA3255 needs a minimum of 18 volts which is doable with a suitable laptop supply but what would you use for batteries? Two 12v SLA's would be a minimum. You would need a charging arrangement as well.
You might want to look at TPSM84205 which is a switching power supply used like a 7805. I used one
in my last project and its pretty quiet and very efficient - it does NOT get hot. Not cheap but doable.
https://www.digikey.com/en/products...1620?s=N4IgTCBcDaICoAUDKBZAHAFjABgKwBoQBdAXyA
G²
I also dive a bit into diy battery packs. So making a 48v pack etc wouldnt be new to me. Thats Why i maybe thought the TPA3255 was perfect. I suspect, if build properly, that it Can deliver the watts for my party speakers, But also Sound really good for the inside hi-fi speakers. That means that i dont have to build more than one pcb for my projekts.. Am i right?
Given what you say something like the TPA3255 would be a prime contender but I suspect you are then looking at getting a premade module rather than diy'ing one from scratch.
Yeah, might have to. Either that or i just copy the reference design, so i can choose my own parts. I want to get into building amplifiers one way or another.