Are you creating a new technological design and need to choose the right device? Unsure whether a microprocessor or a microcontroller will be the best option? There are many things to consider before you purchase, including the data storage, programme memory, power consumption and overall performance. Here, we explore the key differences between microcontrollers and microprocessors that will help you decide which is right for you.
Memory and data storage
A microcontroller has an embedded memory – more specifically an on-chip Flash memory – to store and use the required data. Typically, a microcontroller will have around 2MB of total available memory, which is fairly limited and may not be sufficient depending on the application. However, there are benefits of having a limited amount of memory. For instance, a microcontroller’s start-up speed and programme delivery is quick in comparison to other devices.
On the other hand, microprocessors utilise an external memory to store programme and data information. This means that the amount of memory and data storage you can use is much higher than that of a microcontroller – often hundreds of MB. However, as this is loaded into an external memory chip when the programme starts up, it takes longer for the device to get going than a microcontroller.
Power consumption and supply
Of course, power consumption is a key consideration when it comes to choosing devices. Today, we are seeing more and more microcontrollers being used in small, efficient devices that run on battery power. The draw for developers is that they have the capability to support multiple actions while using extremely low amounts of power.
Microprocessors will typically consumer a greater amount of power, due to the number of external components required for the circuit to operate. Certain microprocessors feature low power modes, but these are still not as low as that of a microcontroller. This means that microprocessors are not suited to battery-powered devices.
Another thing to consider is that a microcontroller will require a single voltage power rail, while a microprocessor will need many different power rails – so you will need to factor this into your design.
Performance and cost
Strong performance is key to any successful technological device. Whether you’re creating a large circuit for a computer or a small circuit for a music player will dictate which device is the most suitable. Those that require high processing power for demanding applications will be best suited to a microprocessor. This is because they are typically rated much higher in terms of Dhrystone MIPS than a microcontroller. For example, a higher level of processing power is likely to be required where the user interface contains image-led graphics and multimedia content.
That being said, the overall cost of a system that uses a microprocessor is higher than the cost of a microcontroller circuit. This is because they usually require more components, more power and more storage capabilities. This means that microprocessors are well suited to performance-driven devices that require a large amount of power, whereas microprocessors are a cost-effective solution in devices needing power-saving capabilities.
Now that you know the key differences between a microprocessor and a microcontroller – you can purchase your parts and get started building your design. Make sure you invest in good quality parts from companies such as RS Components that will ensure your circuit is both functional and affordable.