Motor driver discussion

[vyosypenko]

Hi,

We have some issue with STM32 board and VNH2SP30 motor driver: Logic levels for STM32 are 3.0V (3.3V but the board has IC with a diode which generates 3.0 power supply for STM32 ). According to the datasheet of VNH2SP30 (https://www.st.com/resource/en/datasheet/cd00043711.pdf) all input pins are "5 V logic level compatible inputs". (page1), and "Input high-level voltage 3.25" (table 7). So even we provide 3.0V PWM, this board recognized it as logical 0, and the motor will not be enabled.

Solutions:

1. Use level shifters like this: https://www.ebay.com/itm/3-3V-5V-4-Channel-Logic-Level-Converter-TTL-Bi-Directional-Shifter-Module-10pcs/152613484769?hash=item238878f8e1:g:kN0AAOSwFJBZXdOE:rk:5:pf:0

2. Change the motor driver to other which has "3V-compatible inputs" levels like this: https://www.pololu.com/product/1451 High-level input voltage 2.1 V (table 7). https://www.pololu.com/file/0J504/vnh5019.pdf

As for me, the second solution is better as we don't need to have any extra boards. But the first solution is much cheaper.

Thanks, Vasyl