3 years, 10 months ago.

mBed LPC1768 average supply current

Hi there,

Does anyone know what the average current drawn by the mbed LPC1768 module itself is?

I'm using it to control a automotive sensor array and need to know how much current it draws without outputs so I can spec out a voltage regulator.

Cheers,

Ryan.

3 Answers

3 years, 10 months ago.

Hi Ryan,

I apologize for the delayed response. You can view the supply current values and other limiting values on the LPC1768's datasheet here: https://www.nxp.com/docs/en/data-sheet/LPC1769_68_67_66_65_64_63.pdf (specifically on page 45).

- Jenny, team Mbed

3 years, 10 months ago.

There is significant current draw from the Ethernet interface (much higher than the MCU itself).

There are some examples floating around somewhere on how to power down the Ethernet interface.

3 years, 10 months ago.

Testing a random unit on my desk the current draw is 140mA at 5V.

It's toggling a couple of IO pins and waiting for serial data. All LEDs other than the power on off.

This board isn't designed for low power but you can reduce it a little. By far the biggest saving is powering down the Ethernet phy.

A quick search found this which should help you a lot: https://os.mbed.com/users/no2chem/notebook/mbed-power-controlconsumption/