I am trying to build a sound system with an Arduino uno, DFPlayer mini, and Pyle 240W PLMRA120 amplifier to output through an 8 ohm speaker. I want to use a single power source for both the Pyle amplifier and arduino though the amp requires a 12V power supply and the arduino 5V so I have a step down before the arduino.
You can see in the attached schematic the approach I've taken but I don't get any audio playing. I get a crackle when I plug in SPK1 and SPK2 but no audio playback. I've also tried using the DAC_R and DAC_L from the DFPlayer mini rather than SPK1 and SPK2 but still no audio.
Is there a grounding issue? Or a problem with the single power source?
Have you tested this with just the DFplayer, and with a confirmed good amplifier from an external power source? This way you can establish if your code is working. Then test pieces of your system in isolation and see where your problem is
Is there a car or motor connected to this battery?
Is the df player a stereo device? Should yo mix left and right to convert to mono? (Can be done,with 3 resistors...)
I hate frizzies but yours is very clean, labeled and readable, great job.
Your picture does not show all grounds connected. Also as noted by @runaway_pancake you are powering it wrong which can cause if to do what it wants from nothing to frying. I recommend since the buck converter is just for the Arduino set it for about 8.5V and power it via Vin. This will give you additional filtering etc that will help keep the noise out of the audio when you get it working. The DS3231 would be much happier if you power it with 5V from the arduino. Also you are missing pull up resistors. Some DS3231 boards have 10K others do not.
I left out a key detail, I got the base design from this paper, Low-cost automated call box system to conduct playback experiments for wildlife research and management. In this paper they did not use an amplifier. I would like to add an amplifier as I will use this to project bird calls across a large distance. This is also where I got the detail that the arduino needed a 5V input. @runaway_pancake@gilshultz Thanks for the correction! Obviously, I now see I should read the data sheets for each of these components and not expect this published paper to be correct.
So I've adjusted the step-down from 5V to 8.5V, and moved the DS3231 to the 5V from the arduino as @gilshultz suggested. I also moved the DFPlayer to the 3.3V arduino pin, which according to the DFPlayer mini data sheet seems suitable.
Next I think I need to adjust grounding. I should have my connection from DFPlayer to amp be through the DAC_R/DAC_L terminals to the amp audio input, but each of these needs a grounding back to the DFPlayer, right?
Sorry for the basic questions, I appreciate the help!
