My apologies up front if this question is more appropriate for Orbitty carrier board supplier – unfortunately, I’m not an expert on USB, so not sure where to start.
I need to connect a USB camera and a G3/G4 LTE USB modem to the USB OTG port on Tx2 + Orbitty carrier board configuration. Total current draw from the two USB devices is expected to be up to 865 mA, which is more than the USB OTG port can supply. In this application, space and weight constraints make it difficult to use a powered USB 2.0 hub. Instead, I’d like to splice an external +5V power supply between the +5V and GND lines within a USB cable. In doing so, the +5V line going back into the Orbity carrier board would become an open circuit; however, the ground line would remain unbroken. My question is, will this work? More specifically, will my approach cause any problem for the USB circuitry when it tries to negotiate with connected devices to allocate power? Is there a way in software to disable current sensing on USB port so this injection scheme will work?