Power dissipation in MCU

microcontrollerpower-dissipation

I am posting a screen shot of the abs max rating of the LPC43xx microcontroller. It states that the total power dissipation of the package is 1.5W. I am assuming that the total power dissipation means the power dissipated when all the peripherals and all working inside the MCU. Supposing I have only the I2C working how much would the MCU dissipate in terms of power. Also this chip has regulator power supply and I/O voltage supply.

Should I incorporate the power contribution from both and sum it up, so Preg+PI/O?

Will the total power dissipated be the power of the above + PI2C ?

enter image description here

Best Answer

The maximum power dissipation is a rating of how much power the package can physically dissipate. How the MCU ends up drawing that much power is another matter; for instance, it could be simply a lot of GPIO pins each driving substantial output current.

If you want to compute actual power consumption, you should look at the relevant figures in table 10 for power consumption (for instance, IDD(REG)(3V3)), the graphs in figures 11 through 19, and the peripheral power consumption figures in 10.2. Sum up the relevant figures and multiply by the operating voltage to get a figure in watts.