ADLINK PCI-9820 - Manual (Page 29)

Operation Theory
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4
Operation Theory
The operation theory of the PCI-9820 is described in this chapter, including
the control and setting of signal sources, timebase sources, trigger sources,
trigger modes, data transfers, synchronizing multiple cards, and
auto-calibration.
4.1 Analog Input Signal Source Control
Number of Channels
The PCI-9820 provides two simultaneously sampled analog input channels in
SE (single ended) connection. Each channel can be enabled individually.
Signal Range and Input impedance
The available signal input ranges are ±5V or ±1V, which can be set by
software. All signals are DC-coupled. The input impedance for high-speed
applications should also be considered. The selectable input impedance
values are 50Ω and 1.5MΩ. Please refer to section 3.2 for the details.
4.2 A/D Sampling rate and TIMEBASE Sources Control
The PCI-9820 supports three timebase sources for analog input conversion:
• Internal 60MHz
• External sine wave
• SSI timebase