3 years, 8 months ago.

Digital voltage supply is selectable--how?

The X-Nucleo-IHM02A1 dual stepper motor driver board says: "Digital voltage supply is selectable (3.3 V or 5.0 V) by a 0 Ω resistor and is provided on main board"

I have 5 V logic level (encoder) signals being sent through the stepper motor driver boards. Is it possible for the Nucleo-144 to take 5 V? How? What zero ohm resistor(s) need to be changed?




2 Answers

3 years, 8 months ago.

The digital IO of the STM processors on the Nucleo144 boards are 5 V tolerant. They output at 3.3 V but can take 5 V inputs (with a few exceptions e.g. the analog inputs when in analog mode, the USB pins etc...).

The stepper motor board is designed to work with both Nucleo boards and also with Arduino boards which have 5 V IO. As default it uses 3.3V IO for the control interface to the motor driver chips. If you were to use a processor which needs 5 V IO you would remove SB 40 and fit/close SB 41 (page 4 of the schematics in the lower left). These are an either/or option, never have both or you will break things.

Accepted Answer

(page 5)


posted by Adam Aero 30 Jul 2019
3 years, 8 months ago.

Hi Adam,

Since this is more about platform not Mbed OS, I would suggest you to ask this question on their community, there can give you more correct answer for this.