24v Keypad - Microcontroller

[Sadlercomfort]

Hi guys,

Does anyone know how to interface a 24v keypad to a microcontroller.

Usually I would use a 5v keypad and connect it directly to one of the ports with pull up resistors. However I can only find a 24v one for cheap on farnell so I have to use this.

http://www.farnell.com/datasheets/1804053.pdf

Is this a 24v max rating? Or do i need to use 24v?

Thanks,
Ash

 

[Minder]

Those KB's are passive devices, just tactile switch so 5v or 24v does not really matter, they are set up with a matrix to save on I/O, see the tutor series by Nigel Goodwin Tutorial site.
M.

 

[Sadlercomfort]

Oh okay,

So its safe to say i can use anything from 5V to 24V.

 

[Minder]

As long as you observe the 50ma rating.
Correction, I see they have a ilumination LED they mention 5v for these?
Separate connections.
M.

 

[Minder]

To follow up it appears that the keyswitches are anything up to 24vdc rated, the diode anode/cathode is 5v, I am assuming that there is internal series resistors, it does not mention the inner connections.
M.