Microcontroller

A microcontroller (MC, uC, or μC) or microcontroller unit (MCU) is a small <a href="/facts/Computer/SQe1aK05">computer</a> on a single <a href="/facts/Integrated_circuit/fjn6vg7C">integrated circuit</a>. A microcontroller contains one or more <a href="/facts/Central_processing_unit/Jxp1bqMV">CPUs</a> (<a href="/facts/Processor_core/Jxp1bqMV">processor cores</a>) along with <a href="/facts/Computer_memory/hQKVQ51J">memory</a> and programmable <a href="/facts/Input%2foutput/WQTE8Jas">input/output</a> peripherals. Program memory in the form of <a href="/facts/Flash_memory/Cn8JsStx">NOR flash</a>, <a href="/facts/Programmable_read-only_memory/amoyxIFx">OTP ROM</a>, or <a href="/facts/Ferroelectric_RAM/y32nvhvK">ferroelectric RAM</a> is also often included on the chip, as well as a small amount of <a href="/facts/Random-access_memory/DuD4bxh6">RAM</a>. Microcontrollers are designed for <a href="/facts/Embedded_system/a4muX1wU">embedded</a> applications, in contrast to the <a href="/facts/Microprocessor/Fx9CaQht">microprocessors</a> used in <a href="/facts/Personal_computer/koaYfNce">personal computers</a> or other general-purpose applications consisting of various discrete chips.
In modern terminology, a microcontroller is similar to, but less sophisticated than, a <a href="/facts/System_on_a_chip/1RVvVe6N">system on a chip</a> (SoC). A SoC may include a microcontroller as one of its components but usually integrates it with advanced peripherals like a <a href="/facts/Graphics_processing_unit/PTK1RQVp">graphics processing unit</a> (GPU), a <a href="/facts/Wi-Fi/u94quCsx">Wi-Fi</a> module, or one or more <a href="/facts/Coprocessor/WsVXzAGo">coprocessors</a>.
Microcontrollers are used in <a href="/facts/Control_system/8CEjIDlS">automatically controlled</a> products and devices, such as automobile engine control systems, implantable medical devices, remote controls, office machines, appliances, power tools, toys, and other <a href="/facts/Embedded_system/a4muX1wU">embedded systems</a>. By reducing the size and cost compared to a design that uses a separate <a href="/facts/Microprocessor/Fx9CaQht">microprocessor</a>, memory, and input/output devices, microcontrollers make digital control of more devices and processes practical. <a href="/facts/Mixed-signal_integrated_circuit/cDkjcck8">Mixed-signal</a> microcontrollers are common, integrating analog components needed to control non-digital electronic systems. In the context of the <a href="/facts/Internet_of_things/rwwGAxn3">Internet of Things</a>, microcontrollers are an economical and popular means of <a href="/facts/Data_collection/rEGBdDzj">data collection</a>, <a href="/facts/Sensor/RN8SXbjs">sensing</a> and <a href="/facts/Actuator/mF9qVJJR">actuating</a> the physical world as <a href="/facts/Edge_device/YYjW304H">edge devices</a>.
Some microcontrollers may use four-bit <a href="/facts/Word_(computer_architecture)/2e5umRaj">words</a> and operate at frequencies as low as 4 kHz for low <a href="/facts/Electric_energy_consumption/eEl4r39x">power consumption</a> (single-digit <a href="/facts/Watt/VK8oqRrm">milliwatts</a> or microwatts). They generally have the ability to retain functionality while <a href="/facts/Wait_state/cAzx3jKR">waiting</a> for an <a href="/facts/Event-driven_architecture/THC25H6E">event</a> such as a button press or other <a href="/facts/Interrupt/Mm6C4rpc">interrupt</a>; power consumption while sleeping (with the CPU clock and most peripherals off) may be just nanowatts, making many of them well suited for long lasting battery applications. Other microcontrollers may serve performance-critical roles, where they may need to act more like a <a href="/facts/Digital_signal_processor/YuBXweos">digital signal processor</a> (DSP), with higher clock speeds and power consumption.

Microcontroller open-in-new

Microcontroller