Digital Logic - SR Latch

Introduction: Digital Logic - SR Latch

The SR Latch is a great way to introduce how digital logic works. First you make two NAND Gate which is "Not AND" in logic terms and you can combine them together to make a latch. The way it works is by using the unstable condition to hold the last state or the last pushbutton that was pressed. This introduces memory into the circuit.

Part List

  • Pushbuttons (2)
  • Green LEDs(2)
  • 1,000 Ohm resistors (10)
  • NPN transistors (4)
  • Diodes (6)

How it works

Just press the top pushbutton and the top LED will stay on or press the bottom pushbutton and the bottom LED will stay on.

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    This looks like an awesome gadget, I just wish there were more pictures, and more step by steps. Those two things can really help people fully complete your project!