National Instruments AT-MIO-16X - Manual (Page 81)

Chapter 3 Theory of Operation
© National Instruments Corporation 3-15 AT-MIO-16X User Manual
Data Acquisition Rates
The acquisition and channel selection hardware function so that in the
channel scanning mode, the next channel in the channel configuration
register is selected immediately after the conversion process has begun
on the previous channel. With this method, the input multiplexers and
the PGIA begin to settle to the new value while the conversion of the
last value is still taking place. However, the circuitry does not always
settle to full 16-bit accuracy within the smallest allowed sample period
of 10
µ
sec. Appendix A, Specifications, for specification of settling
times for the AT-MIO-16X in scanning modes.
Analog Output and Timing Circuitry
The AT-MIO-16X has two channels of 16-bit D/A output. Unipolar or
bipolar output and internal or external reference voltage selection are
available with each analog output channel through a register in the
AT-MIO-16X register set. Figure 3-9 shows a block diagram of the
analog output circuitry.