<< return to Pixycam.com

what does the power mosfet do?

Pixy Hardware
#1

Hi,

I am studying the schematic and am confused by what the power mosfet (Q1, NTJD1155L) is for? Isn’t the 5V provided by the computer through USB_VBUS? The circuit seems to imply that VCC_5V is used to power USB_VBUS, controlled by VBUS_EN.

Thanks,
Greg

#2

Hi Greg, the mosfet is there because we have two ways to power Pixy-- through JP1 and through USB. The mosfet can switch off when we’re powering through JP1 so we’re not back-driving power through USB.

thanks!