What’s the Difference Between Microprocessors and Microcontrollers?

What’s the difference between microprocessors and microcontrollers?

Microprocessors and microcontrollers are the internal components of electronic devices. A microprocessor is a very small processing unit inside a CPU. It's a single integrated circuit on a computer chip that performs various arithmetic and logic functions on digital signals. Several dozen microprocessors work together inside high-performing servers for data processing and analytics.

On the other hand, a microcontroller is the basic computing unit inside smart electronic devices like washing machines and thermostats. It's a very tiny computer with its own RAM, ROM, and I/O systems, all embedded on a single chip. It can process digital signals and respond to user input, but its computing capacity is limited.

What are the similarities between microprocessors and microcontrollers?

Microprocessors and microcontrollers are centralized computer chips that provide intelligence to personal computers and electronic devices. They're built with semiconductor integrated circuits and share certain internal parts. 

Integrated circuit

Both microprocessors and microcontrollers are semiconductor components built on an integrated circuit. An integrated circuit is a very tiny square or rectangular chip that contains thousands or even millions of electronic components. Integrated circuits allow engineers to reduce the size of electronic circuits.


Both microprocessors and microcontrollers have a CPU. A CPU is the centralized part of the computer chip that processes instructions provided by applications or firmware. The CPU also has a special arithmetic-logic unit (ALU) module. An ALU calculates mathematical values and evaluates logic problems based on computer instructions. 


Registers are memory modules that the CPU uses for processing. The CPU temporarily stores instructions or binary data before, during, and after they're processed. Both microprocessors and microcontrollers are built with internal registers, although microcontrollers often have more registers than microcontrollers.

Architectural differences: microprocessors vs. microcontrollers

Architectural differences: microprocessors vs. microcontrollers 

Despite taking the form of computer chips, microprocessors and microcontrollers are constructed with different architectures.

Microprocessors are engineered with the von Neumann architecture, where a program and data reside in the same memory module. Meanwhile, microcontrollers use the Harvard architecture, which separates program memory from data space. 

Microprocessors have more integrated circuit components than microcontrollers. This architectural difference affects design considerations for microprocessors and microcontrollers in computing and embedded system applications.

Read about computer chips »  


Microprocessors have no internal memory modules for storing application data. Engineers must connect the microprocessor to external memory storages such as ROM and RAM with an external bus.

A bus is a set of parallel electrical connections that allows the microprocessor to send and receive data from other devices. There are three types of buses:

  • A data bus transmits data
  • An address bus transmits information about where to store and retrieve data
  • A control bus transmits signals to coordinate with other electric components

All three work collectively in a microprocessor system.

On the other hand, microcontrollers are built with internal ROM and RAM memories. A microcontroller uses an internal bus to interact with built-in memory modules. 


Peripherals are timers, communication, I/O, and other capabilities that allow microcontrollers or microprocessors to interact with external components or users.

The microprocessor has no peripherals built into its integrated circuit. Instead, peripherals are connected externally to expand the microprocessor's use cases beyond mathematical and logic processing.

In contrast, microcontrollers connect with on-chip peripherals with an internal controlling bus. This allows the microcontroller to control electronic devices with minimum or no additional parts.   

Computational capacity

Microprocessors are powerful computer chips capable of performing complex computational and mathematical tasks. For example, you can run statistical processing software because the microprocessor supports floating-point operation.

Conversely, microcontrollers have comparatively lower processing power and seldom support floating point calculation. Instead, they focus on implementing specific logic, such as controlling a heater's temperature based on various sensors.  

Other key differences: microprocessors vs. microcontrollers

Microprocessors support versatile computing operations in personal computers and enterprise servers. Meanwhile, microcontrollers allow embedded systems to analyze and respond to inputs in real-time.

When engineers develop systems with microprocessors and microcontrollers, they're mindful of differences like these.

Clock speed

Microprocessors provide high-speed and robust computing capacities for varying applications. A modern computer processor operates in the range of gigahertz (GHz). This allows a computer system to perform complex mathematical calculations and return the results promptly. 

While the microcontroller's speed has increased throughout the decades, it's much less than the microprocessor's processing speed. Depending on its purpose, a microcontroller's clock speed ranges between kilohertz (kHz) to hundreds of megahertz (MHz). Despite the lower speed range, a microcontroller can operate optimally within its dedicated scope of application.

Circuit size

A microprocessor cannot operate on its own. It relies on external parts, such as communication chips, I/O ports, RAM, and ROM, to form a complete computing system. Therefore, a microprocessor-based circuit consists of an address and data bus connecting many peripherals and memory chips. Even with advancements in printed circuit board (PCB) technologies, a microprocessor system requires considerable space.

The microcontroller, however, provides a space-saving design with a simpler circuit. Most of the additional components a microprocessor-based system needs are readily available on the same chip. Rather than using individually separated components, engineers use a single microcontroller when designing electronic devices. This allows more space on the electronic circuit board, which allows engineers to produce compact systems. 

Power consumption

Microprocessors often run at a higher speed than microcontrollers and consume more power, so they require an external power supply. Likewise, a computing system based on a microprocessor unit has a higher total power consumption because of the large number of additional components. 

Meanwhile, microcontrollers are designed to operate efficiently with minimal power. Moreover, most microcontrollers have power-saving features, which microprocessors lack.

For example, a microcontroller can activate the power-saving mode and consumes limited power when not processing data. Microcontrollers can also turn off internal peripherals not in use to save power. This makes microcontrollers ideal for building a dedicated low-power application that runs on stored power.

Operating system

In practical applications, microprocessors require an operating system to provide the appropriate functionalities. Without an operating system, users would have to instruct the microprocessor in assembly or binary language.

Meanwhile, microcontrollers don't require an operating system to run. There are, however, specific operating systems that help mid- and high-range microcontrollers to operate more efficiently. 


Microprocessors handle more diverse communication technologies than microcontrollers. For example, a microprocessor processes high-speed USB 3.0 or Gigabit Ethernet data without a secondary processor.

However, most microcontrollers need a special processor for high-speed data connectivity. 


A microprocessor integrated circuit only consists of the CPU, arithmetic-logic unit (ALU), and registers, which reduces the per-unit manufacturing cost. Meanwhile, a single microcontroller has a more complex internal architecture and is generally more expensive than a microprocessor.

However, a microprocessor-based system is more expensive as it requires additional components. In contrast, a microcontroller is self-sufficient for its chosen application.

The microcontroller requires fewer additional components, which results in cheaper microcontroller-based systems. For example, an air conditioner's circuit board with a microcontroller costs less than a computer motherboard with microprocessors. 

Use cases: microprocessors vs. microcontrollers

Both microprocessors and microcontrollers are useful electronic components when you apply them to the appropriate use cases.

Use a microprocessor if you require robust processing power for complex or unpredictable computing tasks. Microprocessors are used in all types of computing devices like servers, desktop computers, and mobile computing devices. Organizations use servers with many microprocessors for high-performance computing and for running artificial intelligence (AI) applications.

On the other hand, the microcontroller is the better choice if you're building a control system with a narrowly defined scope. Microcontrollers are also useful for systems that require low power consumption. Some microcontrollers can run for months with just a small battery. For example, a smart home system is powered by microcontrollers. Compact devices like drones or portable audio players also contain microcontrollers.

Summary of differences: microprocessor vs. microcontroller





Requires external memory and data storage.

On-chip memory modules (ROM, RAM).


Needs additional parts. Connect with the external bus.

On-chip peripherals (timers, I/O ports, signal converter).

Computational capacity

Capable of complex computing tasks. 

Limited to specific application logic.

Clock speed

Very fast. GHz range.

Fast but slower than microprocessors. kHz to MHz range.

Power consumption

High power consumption. No power saving mode.

Consumes minimal power. Built-in power saving modes.

Operating system

Requires operating systems.

Operating system is optional for some microcontrollers. 


Handles high-speed data transfer. Supports USB 3.0 and Gigabit Ethernet.

Supports low to moderate speed communication. Serial Peripheral Interface (SPI) and I²C. Universal asynchronous receiver-transmitter (UART).


Expensive because of the additional components.

Cheaper because a single integrated circuit provides multiple functionalities. 

Use case

For generic computing, or systems requiring robust computational capacity.

For compact systems, battery-powered, or logic processing devices. 

How can AWS help with your microprocessor and microcontroller development needs?

Amazon Web Services (AWS) supports your microcontroller and microprocessor development needs with relevant resources and infrastructure.

You can use FreeRTOS to create modular microcontroller applications that connect with the cloud. FreeRTOS is an open-source, cloud-neutral, real-time operating system that offers a fast, dependable, and responsive kernel. AWS provides helpful libraries with FreeRTOS, allowing you to integrate Internet of Things (IoT) capabilities in the microcontroller's firmware more effortlessly. 

Amazon Elastic Compute Cloud (EC2) allows organizations to deploy microprocessor-based applications on the cloud. You can scale the computing environment, or instance, according to your application specification and ongoing demand. We provide different types of instances, including those powered by ARM, Intel, and AMD processors, for almost any workload. 

Get started with microprocessor and microcontroller development on AWS by creating an account today.