Figure 9-4 shows an example of a PCB layout for a data acquisition system using the REF35. Some key
considerations are:
- Connect low-ESR, 0.1μF ceramic bypass
capacitors at VIN, VREF of the REF35.
- Decouple other active devices in the
system per the device specifications.
- Using a solid ground plane helps
distribute heat and reduces electromagnetic interference (EMI) noise pickup.
- Place the external components as close
to the device as possible.
- Do not run sensitive analog traces in
parallel with digital traces. Avoid crossing digital and analog traces if possible, and
only make perpendicular crossings when absolutely necessary.
Figure 9-5 shows the pin compatibility with TI REF30xx, REF31xx and REF33xx series references in the
3-pin SOT-23 package when using the REF35xxx family footprint. You must rotate the REF30xx,
REF31xx and REF33xx reference devices by 180º before assembly.