Power and Environmental Requirements
Photon II System Guide 9
3 Power and Environmental
Requirements
Power Requirements
The Photon II’s power is provided by the USB connection. No other
power connection is needed. The USB standard requires the USB port to
provide 2.5 Watts of power to the USB device. The Photon II can
consume as much as to 2.5 Watts. To ensure proper power supply to the
Photon II, it is not recommended that it be used on a hub with other USB
devices.
2.5 watts at 5 volt DC is equivalent to 500mA of electrical current. Some
PC USB-controllers provide the electrical current information. Below is
a bitmap showing the power management of the USB Root Hub with a
LDS-Dactron Photon II under typical operation: