flip flop

This chapter begim a study of the fundamentals of sequential
logic. Bistable, monostable, and astable logic devices called
muLtivibrators are covered. Two categories of bistable devices
are the latch and the flip-flop. Bistable devices have two
stable states, called SET and RESET; they can retain either of
these states indefinitely, making them useful as storage
devices. The basic difference between latches and flip-flops
is the way in which they are changed from one state to the
other. The flip-flop is a basic building block for counters,
registers, and other sequential control logic and is used in
certain types of memories. The monostable multivibrator,
commonly known as the one-shot, has only one stable state.
A one-shot produces a single controlled-width pulse when
activated or triggered. The astable multivibrator has no
stable state and is used primarily as an oscillator, which is a
self-sustained waveform generator. Pulse oscillators are used
as the sources for timing waveforms in digital systems.