The schematics I am following indicate that I need separate switches for each of the outputs but I would really like to use a matrix keypad (it cuts down on cost as I already have one available). If I simply plug in the matrix keypad in place of the existing switches then there are going to be unwanted shorts in the circuit.

I would like to find a hardware solution to this problem so that I can either isolate the each of the swithces in the matrix keypad or come up with a way to "decode" the output of the keypad so that I have individual wires and grounds.

I simply just don't know what kind of IC or component I should be looking for and/or using to make this work.

Thank you for any help you can provide as it is greatly appreciated.