EVAL-AD7902SDZ Datasheet, PDF (26/32 Pages) Analog Devices – On-board reference

UG-608
EVAL-AD7902SDZ LAYOUT
Layout Considerations
When laying out the printed circuit board (PCB) for the AD7902,
follow the recommended guidelines described in this section to
obtain the maximum performance from the converter. Figure 33
through Figure 36 show the recommended layout for the AD7902
evaluation board.
• Decouple all the power supply pins (VDD1, VDD2, and
VIO) and the REF pin with low ESR and low ESL ceramic
EVAL-AD7902SDZ User Guide
capacitors, typically 10 µF and 100 nF, placed close to the
DUT (U1) and connected using short, wide traces to provide
low impedance paths and to reduce the effect of glitches on
the power supply lines.
• Separate analog and digital sections and keep power supply
circuitry away from the AD7902.
• Avoid running digital lines under the device and crossover
of digital and analog signals because these couple noise into
the AD7902.
Figure 32. EVAL-AD7902SDZ Evaluation Board Silkscreen—Top Assembly
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