2025-05-18 11:05 PM
Can we keep VDD33USB keep NC if USB feature not using In STM32H753ZIT6?
If kept NC what may go wrong?
2025-05-18 11:36 PM
NC is usually not the best idea , with any digital input pin;
see ds :
So you could leave it to gnd. But why not set it to vdd ? So later, if you want USB, its there.
2025-05-18 11:54 PM - edited 2025-05-19 1:31 AM
thanks @AScha.3 , I agree on this, I fact i suggested to keep zero ohm and tie it with VDD( 3.3V). but issue is we are in final stage of Gerber generation ( keept this pin NC) . Now need strong reason to modify it now.
also will you check on below snap?
if not used 0v to 3.6V. I not sure if 0V to 3.6V means not we can keep it NC.
adding link of application note
*Getting started with STM32H723/733, STM32H725/735 and STM32H730 Value Line hardware development -
FAQ: Configuring the VDD50USB and VDD33USB pins on... - STMicroelectronics Community
2025-05-19 12:34 AM - edited 2025-05-19 12:37 AM
From ds , 0...3v6 allowed, NC should be no problem for function of cpu.
But as always: a floating input (here power input) is not the "perfect" design idea.