Circuits That Remember

Feedback and latches

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• Memory needs feedback: outputs looping back into inputs.
• An SR latch (two cross-coupled NOR gates) stores one bit.
• Clocked latches become flip-flops, registers and RAM.

Steps

1. Feedback
2. Store a bit
3. Both at once
4. From latches to computers
5. Storing a kibibyte
6. Moore’s law