Specifications

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Page 47

ACS253A-CT

Appendix E: USB—High Power/Low Power

The USB specification allows low power and high power devices to be attached to, and powered through, the USB hub. Power

consumption may exceed the internal power capabilities of the Extender if you attach more than one high power device to the

Remote Unit hub. In such cases, we recommend that you use the supplied power supply unit for powering the USB hub.

The USB specifications allow:

• 100 mA for low-power devices

• 500 mA for high-power devices

The ACS253A-U-xx-R2 can supply up to 500 mA. There is no total power limitation, so consuming more than 500 mA may

overload the internal power supply and shut down the device. This means, you can attach either:

• 1 to 4 low-power units or

• 1 high-power unit

If your total USB power consumption exceeds 500 mA, you need to connect the supplied power supply unit before attaching the

devices.

Using the power supply unit, you may attach:

• 1 to 4 high power units or

• 1 to 4 low power units or

• Any combination of these

Each port has a regulated power limit of 500 mA.