collapse

Author Topic: Feng - Mini Amp using PAM8403 (2x 3 Watt)  (Read 2867 times)

blackcorvo

  • Elite
  • ****
  • Posts: 115
  • Chip Points: 5
    • View Profile
    • My Youtube Page
Feng - Mini Amp using PAM8403 (2x 3 Watt)
« on: April 14, 2016, 12:00:59 AM »
Recently I started working on a project that required a small, 5-volt stereo amplifier for sound, so I decided to buy a bunch of them to have a few spare ones in case anything caught fire or whatever.
After playing with one of them for a while, I decided to try and make a guitar amp out of it.

Here's the result:

Sample (Guitar: Vintage V100GT, bridge pickup)

Images of the test setup, schematic and (possible) layout in perfboard:

http://i.imgur.com/fiaXOBB.jpg
http://i.imgur.com/QOeLUjm.jpg
http://i.imgur.com/8pOCXgc.png

As funny as it may sound, the name came from me bashing my fingers on the keyboard after drawing the schematic, half-awake, at 4AM. It was not a joke about the power amp being from chinese manufacture at all.
« Last Edit: April 21, 2017, 01:44:24 PM by blackcorvo »

tonyharker

  • Elite
  • ****
  • Posts: 139
  • Chip Points: 18
    • View Profile
Re: Feng - Mini Amp using PAM8403 (2x 3 Watt)
« Reply #1 on: April 14, 2016, 05:31:05 AM »
Does the TL072 work OK at 5v as the datasheet shows a minimum of about +/- 3.5v (7v total)? The TL062 would be better as this shows a supply of less than +/- 2v. The LM358P would also be suitable it has a minimum supply of +/- 1.5v.

blackcorvo

  • Elite
  • ****
  • Posts: 115
  • Chip Points: 5
    • View Profile
    • My Youtube Page
Re: Feng - Mini Amp using PAM8403 (2x 3 Watt)
« Reply #2 on: April 14, 2016, 03:06:06 PM »
Does the TL072 work OK at 5v as the datasheet shows a minimum of about +/- 3.5v (7v total)? The TL062 would be better as this shows a supply of less than +/- 2v. The LM358P would also be suitable it has a minimum supply of +/- 1.5v.

I did not notice any problems with it working at 5v, but it's good to have other options. I simply used what I had in hands.
The worst that might be happening is that the TL072 is not as linear as it would be at 7v, but that isn't exactly a bad thing when it comes to guitar circuits.

J M Fahey

  • SSGuitar Global Mod
  • Legendary
  • ****
  • Posts: 4142
  • Chip Points: 429
    • View Profile
Re: Feng - Mini Amp using PAM8403 (2x 3 Watt)
« Reply #3 on: April 15, 2016, 09:15:19 AM »
Cool project irmão  :dbtu:

That said, I'm also amazed that TL072 works at all with 5V ; TL062 is better suited and LM358 is *designed*  to work on 5V single supply as mentioned by tonyharker .

blackcorvo

  • Elite
  • ****
  • Posts: 115
  • Chip Points: 5
    • View Profile
    • My Youtube Page
Re: Feng - Mini Amp using PAM8403 (2x 3 Watt)
« Reply #4 on: April 15, 2016, 11:20:17 AM »
Cool project irmão  :dbtu:

That said, I'm also amazed that TL072 works at all with 5V ; TL062 is better suited and LM358 is *designed*  to work on 5V single supply as mentioned by tonyharker .

The minimum voltage usually stands for the device working linearly. Not recommended for precision circuitry, but guitar preamps are much more forgiving.
I do not have a proper way to test how much the linearity changes, however.

 

* User Controls

 
 
Welcome, Guest. Please login or register.
Did you miss your activation email?

* Recent Posts

Z-MATCHER 100W IMPEDANCE MATCHER by Loudthud
[September 16, 2019, 04:42:44 PM]


Hybrid valve and TPA311x by jfetter
[September 13, 2019, 03:29:50 PM]


Marshall 5010 Needs Help by Jazz P Bass
[September 13, 2019, 12:12:27 AM]


Do you need a low pass filter in your amp when you already have the eq? by slimjohnny
[September 11, 2019, 06:01:57 AM]


Gallien Kruger GT200 by mandu
[September 10, 2019, 06:31:10 AM]

* Sponsors