Latches are called memory devices because they have the capability to store one bit of data for as long as the device is powered. They are bistable devices, meaning they have two stable states (representing a binary 0 or 1) and can "latch onto" or hold this state until changed by an input signal. This ability to retain state information effectively makes them memory elements in digital circuits.
How Latches Store Memory
- Latches have feedback circuits allowing them to remember the last input applied.
- When an input sets the latch, its output holds that value even after the input changes.
- This stored state persists as long as power is supplied to the device, functioning as a one-bit memory.
Difference From Flip-Flops
- Unlike flip-flops, which are clocked and trigger on clock edges, latches are level-sensitive and can hold information asynchronously.
- Because of this, latches are sometimes referred to as transparent or level-sensitive memory devices.
In summary, latches are basic storage components in digital electronics that maintain a single bit of memory through their bistable latch mechanism and feedback structure.
