I've tried running two of these (actually TPA3118) mono boards for a stereo amp and ended up with just a ton of power supply noise. Is there a way to overcome this?
I have a situation where I'd like to run 3 of these boards on one supply.
I have a situation where I'd like to run 3 of these boards on one supply.
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You may have noise due to ground loops. We really need to see a diagram of your connections (both power and audio) before trying to diagnose. The particular power supply and TPA3118 boards being used would be helpful too.
I just jumpered the + and GND supply connections between the two boards. The signal RCA grounds are shared between TPA3118 boards and the positive signal L + R channels are fed by an mp3 player (its own battery powered).
Should I be able to power 3 boards supplied in parallel by a 24VDC 10-20amp supply? I'm not so concerned about the current requirements with my question... more will it work without clock noise etc? I know I've seen something about Master/Slave clock settings on these boards but don't know enough about it. In this case, all 3 boards would have the same input signal (also in parallel).
Should I be able to power 3 boards supplied in parallel by a 24VDC 10-20amp supply? I'm not so concerned about the current requirements with my question... more will it work without clock noise etc? I know I've seen something about Master/Slave clock settings on these boards but don't know enough about it. In this case, all 3 boards would have the same input signal (also in parallel).
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You are right ... It is a track to take into account ... (master, slave).
See the Texas instrument doc, for more info.
8.2.2.2 Select the Amplifier Gain and Master/Slave Mode In order to select the amplifier gain setting, the designer must determine the maximum power target and the speaker impedance. Once these parameters have been determined, calculate the required output voltage swing which delivers the maximum output power. Choose the lowest analog gain setting that corresponds to produce an output voltage swing greater than the required output swing for maximum power. The analog gain and master/slave mode can be set by selecting the voltage divider resistors (R1 and R2) on the Gain/SLV pin.
So the boards will have clock noise if not set to slave on amp boards #2 and #3? I'm not as concerned about optimal gain (lowest noise floor or minimum distortion) in this case. But I would like to make sure there's no clock noise.
Ok, we agree.
You would (only) need to change the mode of each board.
I had the same concern with the 3e audio board ...
It was easy to do, at least for their boards.
http://www.3e-audio.com/wp-content/uploads/2018/07/DS_EAUMT-0260-2-A_Rev1.0.pdf
You would (only) need to change the mode of each board.
I had the same concern with the 3e audio board ...
It was easy to do, at least for their boards.
http://www.3e-audio.com/wp-content/uploads/2018/07/DS_EAUMT-0260-2-A_Rev1.0.pdf
Would love to know more about this because I plan on doing the same setup, have you gotten solutions yet? which board do you have?
I see it as a ground loop (digital clock or switching noise passed). However it is possible to gang several off of one supply since there are stereo, 2.1, and probably 5.1 versions using this chip out there.
It looks like on the data sheet, SYNC and SLAVE are the important pins. They show a 2.1 configuration with 2 of these chips (one stereo and one mono) and I assume using the same PSU.
Did you check how you connected input signal, on other two amps I wouldn't connect ground wires on input side, only hot wire (or signal wire).
You will have only one point where you referenced input signal to ground plane of your amp boards.
Power ground is your reference between the amp boards, so you could not connect on all boards input signal ground, it will create ground loop on your application. I would try this and see what happens. Only connect signal gnd wire on one board (three board you are using) and two other leave ground float on side where input signal is connected to the amp (on signal source, connector side, you have to connect ground to it's place, use coax cable to minimise noise on your hot signal wire).
You will have only one point where you referenced input signal to ground plane of your amp boards.
Power ground is your reference between the amp boards, so you could not connect on all boards input signal ground, it will create ground loop on your application. I would try this and see what happens. Only connect signal gnd wire on one board (three board you are using) and two other leave ground float on side where input signal is connected to the amp (on signal source, connector side, you have to connect ground to it's place, use coax cable to minimise noise on your hot signal wire).
Years ago a TI technician told me to forget about the master slave issue. No problem to run two or more on one supply. It will not lead to audible noise issues. Noise with these amps are ground loops in hardly any case.
You would have just the same problems with any A/B "analog" amp. Ground loops are made by any beginner building an amp from more than one module and sometimes very hard to spot, even for professionals.
First rule, only one ground wire to ALL inputs.
You would have just the same problems with any A/B "analog" amp. Ground loops are made by any beginner building an amp from more than one module and sometimes very hard to spot, even for professionals.
First rule, only one ground wire to ALL inputs.