Powering a tpa3116d2 blue board with toroidal
Any help would be much appreciated. I’ve modded a blue board with great success. But... I don’t know how to power it. I’ve got a toroidal transformer with four input wires and no problem hooking it up to 230v. It has dual 9v out (four wires) which will be used as 18v. Will this work or do I create an -18 -0- +18 function in doing so? The blue board only has dc+ and ground in.
Is it possible and if so can somebody explain to child how and what other parts are needed to make it a useful power supply?
After modding the board it’s been tested with a small power supply of 6V so I know it makes sound. Now I wanna build a proper power supply with enough juice.
Any help would be much appreciated. I’ve modded a blue board with great success. But... I don’t know how to power it. I’ve got a toroidal transformer with four input wires and no problem hooking it up to 230v. It has dual 9v out (four wires) which will be used as 18v. Will this work or do I create an -18 -0- +18 function in doing so? The blue board only has dc+ and ground in.
Is it possible and if so can somebody explain to child how and what other parts are needed to make it a useful power supply?
After modding the board it’s been tested with a small power supply of 6V so I know it makes sound. Now I wanna build a proper power supply with enough juice.
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You'll need a bridge rectifier (or just two beefy diodes for a full-wave rectifier) and some bulk filter caps in-between the transformer and the amp board.
Any chance you could post some photo of the transformer you have, and any markings / labels it might have on it?
With a dual-9VAC, you can just connect those in series (if you get the phasing right - that's the reason for my question above), which would give you 18VAC. After rectification, that should end up somewhere around 25-26V - that's pretty much "on the edge", according to the TPA3116/8 ratings.
Parallelling the windings would give you 12-13V, which would be safer, but would limit the maximum output power.
Any chance you could post some photo of the transformer you have, and any markings / labels it might have on it?
With a dual-9VAC, you can just connect those in series (if you get the phasing right - that's the reason for my question above), which would give you 18VAC. After rectification, that should end up somewhere around 25-26V - that's pretty much "on the edge", according to the TPA3116/8 ratings.
Parallelling the windings would give you 12-13V, which would be safer, but would limit the maximum output power.
Thanks! That’s my mistake thinking 18 vac would generate 18vdc. It’s a triad transformer @5.something A
VPT18-5560 Triad Magnetics | Mouser Sverige
VPT18-5560 Triad Magnetics | Mouser Sverige
18vac transformer is about perfect for the tpa3116. it gives 25.5v but there will be voltage drop across the rectifier, so you will end up somewhere between 24 and 25v. Use a meter on the caps to be certain though. The tpa3116 recomends 26v as max operating voltage, but 30v as absolute max input voltage, so anything over 26 is risky.
As to the next question / follow up for your +/- 19v needs... you cannot really get that with this transformer. +/- means it wants a + DC and - DC supply. Yo can get to about +/- 12v after diode drop if you ran the 9v secondaries.
As to the next question / follow up for your +/- 19v needs... you cannot really get that with this transformer. +/- means it wants a + DC and - DC supply. Yo can get to about +/- 12v after diode drop if you ran the 9v secondaries.
I'm confused. But then again I do not understand electronics. That's why I haven't hooked everything up yet.
A toroidal (or any transformer) accepts AC current and puts out AC current. Right or wrong?
My toroidal with 2 secondary windings should be able to deliver 2x9V or +18 0 -18 if connected in series? The preamp I have runs off AC current as far as I can tell. Inputs on the preamp bord is +, ground, - (3 connections)
Could I just hook the transformer up to the preamp or do I need further components to make a safe connection?
If Jared thinks it perfect for the amp board I'm much more inclined to read up on how to hook it up in series and convert to DC to power the amp board.
A toroidal (or any transformer) accepts AC current and puts out AC current. Right or wrong?
My toroidal with 2 secondary windings should be able to deliver 2x9V or +18 0 -18 if connected in series? The preamp I have runs off AC current as far as I can tell. Inputs on the preamp bord is +, ground, - (3 connections)
Could I just hook the transformer up to the preamp or do I need further components to make a safe connection?
If Jared thinks it perfect for the amp board I'm much more inclined to read up on how to hook it up in series and convert to DC to power the amp board.
yes, any transformer takes in AC and outputs AC.
Your preamp probably does not run off of AC, it probably runs off of a negative and a positive DC supply, ie +/- 19v DC.
Remember we are discussing using the transformer to a bridge rectifier to a capacitor bank and then to whichever component you want to power. FWIW a laptop power supply from amazon is under $10 and works well for the tpa3116 boards.
Your preamp probably does not run off of AC, it probably runs off of a negative and a positive DC supply, ie +/- 19v DC.
Remember we are discussing using the transformer to a bridge rectifier to a capacitor bank and then to whichever component you want to power. FWIW a laptop power supply from amazon is under $10 and works well for the tpa3116 boards.
Thanks for all the input. At the moment I’m not qualified to use the transformer. That is obvious to me. Will use two bricks for now. I have 2 that will power the boards so I’ll hook it up that way for now. Seems to be the safe way at the moment.
Don’t know about the preamp. I’ll connect it and compare the sound quality with and without it. If it’s not an improvement I’ll find another use for it.
Don’t know about the preamp. I’ll connect it and compare the sound quality with and without it. If it’s not an improvement I’ll find another use for it.
Took me awhile but the amp is hooked up. No enclosure at this point but I have made power supply and added a volume control and a fuse. I feed the power supply with 18V from the Toroidal and it gives me 24.9VDC 5,56A. Not optimal but within specs for the board. No preamp at this point. Will get a cheaper transformer for the preamp if I decide I need it. Just hooked up the amp to some old speakers found in the attic. Can’t really comment on sound quality at this point but it’s working nicely and played for about an hour so it seems safe.
WXN thanks for the info about not running the preamp from the same transformer. I actually been thinking about such things but fortunately I’ve never tried cause I was unsure. Now I know and will never try it.
WXN thanks for the info about not running the preamp from the same transformer. I actually been thinking about such things but fortunately I’ve never tried cause I was unsure. Now I know and will never try it.
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