PCB Rubber Keypad contact debouncing

Discussion in 'The Projects Forum' started by omairkha, Jul 15, 2011.

  1. omairkha

    Thread Starter New Member

    Jul 15, 2011
    Hi Everyone,

    I am making my very first project using PCB contacts for a rubber keypad and was wondering if there are any debouncing considerations that need to be met.

    Typically for a mechanical NO switch I have used the RC method which works great for those switches.

    Does something similar need to be done for PCB contacts? I would think that the rubber keypad and PCB contact would not have the debouncing issues like we see in mechanical switches but since I have no prior experience in working with these I wanted to double check.

    The layout will be in a matrix form very similar to this schematic:

    Thanks in advance for the help!
  2. praondevou

    AAC Fanatic!

    Jul 9, 2011
    Just googled it. Yes, they seem to have the bouncing issue as well, <12ms to <20ms typically.

    google: Elastomeric Keypads contact bounce
  3. coryfoss

    New Member

    Jun 17, 2011
    Maxim makes switch debouncers; MAX6816, MAX6817, MAX6818.