... SupplySize under 52”(include 52”)USB or PS/2 Interface, power ripple max.200mV rmsSize above 52”(52” not included): external ... AC-DC power adaptorInterfaceFull Duplex USB 2.0 (Full Speed) Plug and play ... Rate: 9600, 8 Data Bits, 1 Stop Bit, No Parity Power<1.5W, operating current<300mAElectrostatic Protection15 kV air / 8 kV ...