Isn't the Electronic Controller Unit (which are used in automotive applications) a Microcontroller it self?

What is the difference between them in architectural point of view?

  • 6
    \$\begingroup\$ What is the difference between a car and an engine? Isn't a car just an engine itself? \$\endgroup\$
    – DKNguyen
    Commented Jan 10, 2020 at 14:49
  • \$\begingroup\$ go to google image search and search for pictures of "MCU" and "ECU". Spot the difference. \$\endgroup\$ Commented Jan 10, 2020 at 14:53
  • 1
    \$\begingroup\$ Also, first item on "components of an ECU" on the wikipedia page lists "microcontroller". So, not really a great lot of research here! \$\endgroup\$ Commented Jan 10, 2020 at 14:54
  • \$\begingroup\$ An MCU will have a microcontroller inside it. I guess they could make one out of discrete logic but they definitely won't bother. \$\endgroup\$ Commented Jan 10, 2020 at 15:03
  • \$\begingroup\$ MCU = Microcontroller Unit = Microcontroller. MCU is just used to differentiate between MCU and MPU (microprocessor unit) which usually doesnt have integrated memory / peripherals etc \$\endgroup\$
    – andowt
    Commented Jan 10, 2020 at 15:09

2 Answers 2


A Microcontroller is an integrated circuit (IC) that is usually a system on chip (SOC) meaning its processor core, memory and IO are all inside one discrete package. Microcontrollers are generic so to use them for specific functions they require supporting hardware and software.

In comparison an Electronic Control Unit (ECU) is a general term that abstracts from the hardware beneath it.

A Microcontroller can be used to make an ECU by integrating it on a circuit board with appropriate physical connectors, custom software, power circuitry and mechanical packaging. However an ECU could instead use an FPGA, mini-PC or purely analogue hardware


A microcontroller is just a single chip. An ECU consists at least of:

  • a metal enclosure
  • printed circuit board
  • microcontroller(s) or microprocessor(s)
  • power supply
  • protection components

These are two different things. Just like CPU != laptop.

This is what an ECU looks like (and the biggest chip is likely the MCU or MPU):enter image description here



Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.