Simple AND Gate.

Simple AND Gate with LED. Shows the working of an AND gate with a 5v source. I used 2 pulldown resistors to give the AND gate the LOW input when the switches are open, otherwhise they would be floating and weird things can happen. Such as the AND gate detecting a high input when floating, making the LED turn on even when the switches are open. The AND gate OUTPUT turns HIGH "only" when both INPUTS are HIGH. ----------------------------------------------------- Please bare in mind (altough not showing here) that besides the INPUT and OUTPUT pins the AND gate also has VDD (5Volt) and VSS (Ground) pins which need to be connected to 5 Volts and GROUND. This AND gate would have 5 pins. 1 VDD (5volts) 2 VSS (Ground) 3 Input pin. 4 Input pin 5 Output pin. The AND gates come in a variety of "packages" (ic's). For example a AND Gate with 3 or 4 INPUTS. There are also IC'S with 2 or more AND Gates on 1 IC.

published 11 years ago