Is it possible to solder LEDs to this chip?

Question

Do it yourself

I want to make a mini keyboard with two mechanical switches on this board , but that's not the problem, I would like to know where to solder the LED on this board and would like to find a circuit for it. I searched the Internet, but I did not find anything.

Answer 1

This is not a microcircuit, it is a board, but the microcircuit here is a round black drop, it is in it that all the logic is embedded, you will not find its diagram or specification anywhere as it was made to order for a specific keyboard model, only reverse engineering with a multimeter and oscilloscope.

Answer 2

The keyboard is of a matrix type:
R0,R1....Rn are strings.
C1,C2....Cn are columns.
When a row and column are closed, the board understands that a key has been pressed.
Make a table in Excel, close Cx c Ry in turn - see which one is pressed and write it down.
LEDs - there are 3 of them - most likely they have a common "+" (the photo does not show where it goes). You can just try - there are only 2 options for connecting them - they flash briefly during initialization.

Answer 3

You can solder LEDs. I allow. As you wish. Anywhere. But not the fact that it will work.
And yes, I disclaim responsibility for the consequences.