Microcontrollers, also referred to as MCUs (microcontroller units), are embedded semiconductor devices used in circuit board design.

What is an AVR microcontroller, and how does it differ from other types?

An AVR microcontroller refers to a specific type of architecture design, initially developed by the Atmel corporation in 1996 and since engineered through numerous stages of improvements, refinements and iterations.

AVR microcontrollers are very widely used today in all kinds of embedded systems and circuits, having become especially popular in recent years due to their inclusion in many Arduino hardware products, a type of open development platform aimed chiefly at hobbyist and educational applications, robot builders, experimenters and small system developers.

Other popular uses of AVR microcontrollers include numerous automotive applications, including security, safety, powertrain and in-car entertainment systems, as well as several types of desktop computer and console controllers and other peripherals

Although they can be thought of in very general terms as a sort of miniaturised ‘computer' component embedded as part of a powered integrated circuit (IC), microcontrollers themselves are relatively limited in scope. They're chiefly used to perform repetitive, single-function tasks requiring only limited clock speeds and comparatively low memory speeds to execute.

AVR microcontrollers are available with different packages such as through hole mounting and surface mount. AVR was one of the first type of microcontroller to use on chip flash memory for program storage instead of one-time programmable ROM, EPROM or EEPROM which was used by other microcontrollers at that period.

AVR Microcontrollers include:

• TinyAVR - these are small with less memory and ideal for simple programming
• MegaAVR - these are popular due to the amount of memory, more inbuilt peripherals and ideal for more complex programming
• XmegaAVR - ideal for more complex programming where large program memory and a higher speed is needed