Agilent Technologies E8257D, Руководство пользователя

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246 Chapter 12
Peripheral Devices
N5102A Digital Signal Interface Module
Clock Timing for Parallel Data
Some components require multiple clocks during a single sample period. (A sample period consists of
an I and Q sample). For parallel data transmissions, you can select one, two, or four clocks per
sample. For clocks per sample greater than one, the I and Q samples are held constant to
accommodate the additional clock periods. This reduces the sample rate relative to the clock rate by
a factor equal to the clocks per sample selection. For example, when four is selected, the sample rate
is reduced by a factor of four (sample rate to clock rate ratio).
Figure 12- 4 demonstrates the clock
timing for each clocks per sample selection. For input mode, the clocks per sample setting is always
one.
Externally Supplied Clock
NOTE : Use only one of the two signal generator frequency reference inputs.