SI535X-20QFN-EVB Datasheet, PDF (4/14 Pages) Silicon Laboratories – Fully-powered from a single USB port

Si535x-20QFN-EVB
5. Clock Outputs
Outputs must be measured with a high-impedance scope probe. A ground test point is provided 0.3" away from
each clock output for ideal measurement. Most scope probes have a ground clip attached to the probe with a 3–6"
length of cable. Use of these ground clips is not recommended since the ground reference is electrically far from
the probe tip, especially for frequencies greater than a few Megahertz. Figure 2 shows the ideal measurement
practice. Note that the probe ground closest to the probe tip is used as the reference.
Clock voltage levels can be 2.5 or 3.3 V depending on the VDDOx VOLT_SEL jumper selection.
Figure 2. Measuring Output
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Preliminary Rev. 0.1