i have this keypad design and it works fine. i need to know why there is the 1K resistors. any help?
G garlitos Jun 7, 2013 3 Joined Jun 7, 2013 Messages 3 Jun 7, 2013 #1 i have this keypad design and it works fine. i need to know why there is the 1K resistors. any help? Attachments Keypad.JPG 33.6 KB · Views: 143
davenn Moderator Sep 5, 2009 14,254 Joined Sep 5, 2009 Messages 14,254 Jun 8, 2013 #2 they are either pull up or pull down resistors ( depending on if they are going to the +V rail or the 0V rail) The chip that scans the keyboard keys will see wither +V or 0V till the key is press when the opposite polarity is read Dave
they are either pull up or pull down resistors ( depending on if they are going to the +V rail or the 0V rail) The chip that scans the keyboard keys will see wither +V or 0V till the key is press when the opposite polarity is read Dave