12 BUTTON KEYPAD

I'm quite satisfied with the quality and function. It's new in package, no problems at all, but this wasn't designed to work with, say, the EDE1144 KeyPad Encoder IC. This keypad has one common pin and one output in for each key. Grouped by column, the pins are (pin=[key]): 1=Common, 2=N/A, 3=[*], 4=[7], 5=[4], 6=[1], 7=[0], 8=[8], 9=[5], 10=[2], 11=[#], 12=[9], 13=[6], 14=[3]

I have to admit, I like this little keypad.

First off, this keypad does not employ a matrix design. Instead, when a key is pressed pin 1 is shorted to one of the other 12 pins. This is a simple method, but requires more connections over a matrix keypad. Depending on your application, this can be a drawback or a benefit.

The construction of the keypad is sturdy enough for most applications and the keys feel good under the finger. The travel distance for the keys is sufficient to provide good feedback.

Overall this is a fairly simple keypad that’s not too difficult to integrate into a circuit. And, if you’re in a hurry, you can also get a decoder / encoder designed to work with this keypad from NeoLoch.

Overall, I like the keypad and will continue to use them.

converter pin available, try this.
Connect the common pin to a 1k ohm resistor which is connected to +5 volts. Connect each pin to a different value resistor, for instance connect 0 to 100 ohms, 1 to 220 ohms, 2 to 330 ohms, etc. Now connect your adc input pin to the common (junction of the 1k resistor and the common of the keypad).
When you are not pressing anything the adc will read full voltage, When you press the zero key, it will read 0.45 volts, when you press the 1 it will read 0.83 volts, etc. Of course you'll have to translate the value from the adc pin to voltage based on the resolution of the adc.
So for the price of 12 resistors you only need to read one pin.

You can use a 74150 or a pair of 74x251's to scan the 12 inputs as if it were matrix encoded.
I haven't bought on of these (yet) but see no reason why it wouldn't work in a scanned application with a bit of external glue.

I am not able to figure out the pin configuration of 12 key, key pad with 8 terminals. i think it should me matrix encoded.