Hey! I need to know how to convert a matrix keypad to one that has separate connections for each key.
For those who don't understand, My current one looks like this:
1 2 3
4 5 6
7 8 9
* 0 #
| | | | | | |
^^^^ 7 Pins^^^^
I need to have 13 pins, one for each number and a Com.
If anyone has a conversion circuit or a data sheet on how it works, I would love to hear from you.
I am unsure of which pin is which. I think that your keypad may be the same as the one on the tech-supplies website (www.tech-supplies.co.uk). This may tell you which pin is which/for what button e.c.t
To find the keypad go to the components section and click on switches.
Use 74C922 IC which is a matrix keyboard decoder. Its output is in 4-bit binary format which you can convert it to 13 lines using binary to deimal converter IC.