Saturday, November 12, 2016

HDMI to VGA Converter, an other Upcycling project

One does not simply trash things at home, every object that can be repaired should be.
Recycling is a thing, Upcycling is another.
  • Recycling is trashing unused or broken goods into pieces, revert them to raw material and use them to rebuild new things
    Usually you can't do it at home.
  • Upcycling is reusing things, either as is, or using parts of them to make others. That's something we can all do, the only things needed are time and will.
  • Upcycling in hight-tech is not only about being "Green" (and where is "Green" in playing with broken highly toxic high-tech materials?), not about saving money either (that converter is less than 10€ on ebay).
    It is more about being able not to throw away unused goods but give them another life.


HDMI to VGA + Audio converter
Why upcycling it?

I didn't have any of those HDMI to VGA converter, and they can come in handy sometimes. I found this one torn down, without its box, and some wires partially ripped off.
It was time to rebuild it.


The mod
Upcycling isn't only repairing but improving too

Beside repairing the converter, I got it modded with an external 5V 500mA input (USB).


Why adding that external 5V power supply, doesn't it gets its power from HDMI ?

HDMI 1.3 standard states the following limits: [source]

This converter is based on the LT8511A chip to convert HDMI digital signal to VGA+Audio analog signals (considering the datasheet, this chip is meant to be powered by an external source...)
This converter is used a lot by Raspberry Pi users that complain about burning a 200mA max rated diode with it and similar converter chips when powered directly by the HDMI input.
==> Looks like it draws a lot more than the 10~50mA expected, As my devices with HDMI output are quite old (the most recent is from 2013) I didn't want to risk the source in the eventuality it doesn't have any over-current protection.


Finding where to solder the +5Vin and mass wires

From the HDMI documentation we know that +5V is coming to the pin 18. Luckily the pins were numbered on the board, after checking continuity with a multimeter, pin numbered 18 was actually pin18 +5V as expected.



Testing

The USB cable used is from a R.A.T.5 mouse

The converter is detected as LTM 40" 1920*1080 display when plugged alone.
When an external display is plugged in, the converter passes through the display specs to the PC:



Finding a case

To stay in the same idea, I couldn't simply go an buy a case. So I took the first plastic case that was there: a battery case for a led strip light (that has already been re-purposed)
Here is the result:

Yeah, Hot glue everywhere...
PS: the audio works well too


Conclusion
Not pretty, but it works.

The result may not be pretty, but it definitely works well. And it proves again that something that was meant to be recycled could be still used after some repair and work on it.
This project has been 99% made out of trashed materials: even the screw is from an old electronic component, only hot glue and solder aren't.
PCBs are hard to recycle, so using a device longer and/or repairing it is "greener" than buying a new device -and paying a few € cents of "green tax" regardless the human work cost of it-.

Whenever possible:
  • Don't trash,
  • Don't recycle,
  • Upcycle!