© National Instruments Corporation C-1 DAQCard-1200 User ManualCPower-Management ModesThis appendix describes the power-management modes of theDAQCard-1200.• Normal Mode—This is the normal operating mode of theDAQCard-1200 in which all the circuits are fully functional. Thismode draws about 150 mA from the 5 V supply (about 750 mW).• Power-Down Mode—In this mode, the digital circuitry is powered onand is functional. The analog input and output circuits are powereddown by setting the PWRDOWN bit in the PCMCIA CardConfiguration and Status Register. You can set the PWRDOWN bit byusing the DAQPOWER utility that is shipped with NI-DAQ. UseDAQPOWER-D to power down and DAQPOWER-U to power up theDAQCard-1200. This utility is also available in Windows and isinstalled whenever you install NI-DAQ. Typically, the analog suppliesare not reduced to zero; negligible power is supplied to the analogcircuits. This mode draws about 50 mA from the 5 V supply (about250 mW).Table C-1 shows the effects of different power-management modes on theDAQCard-1200 circuits.Table C-1. DAQCard-1200 Power-Management ModesNormal Mode Power-Down ModeAnalogInputFunctional. Defaults to bipolar (±5 V)RSE. Protected to ±35 V.Impedance > 1 GΩ.Nonfunctional. Draws negligible power.Protected to ±25 V. Impedance = 4.7 kΩ,which is the input protection resistance.AnalogOutputFunctional. Defaults to bipolar (±5 V)RSE. Output of each DAC remains at 0 V(within 110 ms of card insertion) untilthe first update is performed on thatDAC. Short circuit protected to 80 mA.DC impedance = 0.5 Ω.Nonfunctional. Draws negligible power.Output of each DAC is ideally 0 V, butmay get some negligible value. Shortcircuit protected to 80 mA. Assumeimpedance = 0.5 Ω.
