What Is a Buffer in Electronics?

In general usage, a buffer is something that serves as a protective barrier. There are at least two different meanings for the word in electronics vernacular. A buffer in circuit design is an amplifier that provides an interface between mismatched circuit elements. In computer science, the term refers to a memory device used for temporary storage. It could also be an area of general memory that a computer program allocates for holding large amounts of data it's processing.

A buffer is a unity gain amplifier packaged in an integrated circuit. Its function is to provide sufficient drive capability to pass signals or data bits along to a succeeding stage. Voltage buffers increase available current for low impedance inputs while retaining the voltage level. Current buffers do just the opposite, keeping the current the same while driving high impedance inputs at higher voltage levels. In either case, the buffer protects and the output of the supplying device while providing a sufficiently robust signal to the next stage. Some data buffers are bi-directional, allowing data to pass in either direction. Others are tri-state devices with a disabled state that enablese several device outputs to connect to the same input.

In computer architecture, a buffer is an element or segment of memory that temporarily holds data until the processor is ready to perform some operation on it. Some buffers are dedicated memory locations or devices built into the machine. Computer programs also dynamically allocate areas of general-purpose memory as buffers. Streaming applications, for example, use buffers to queue up large amounts of data for the streaming of audio or video to ensure a supply of information in case of delays.