General
Review and verify the following for the custom
schematic design:
- Reviewed
above "Common checklist for all
sections" section of the user's guide
- Addition
of the required number of bulk and decoupling (high
frequency) capacitors and ferrite filters
- Package
and value used for the capacitors
- Voltage
rating of the capacitors used considering derating
(> twice the worst-case applied voltage is a
commonly used guideline)
Schematic Review
Follow the below list for the custom schematic
design:
- All
processor power rails use bulk and high frequency
decoupling capacitors. The critical power domains
that require the focused attentions are the low
voltage, high current domains (VDD_CORE).
- As a
starting point, the recommendation is to follow the
validated EVM, or PDN application note. When there
is difference between the EVM and PDN, the
recommendation is to follow the PDN. When
information is not available in the PDN, follow the
EVM implementation.
- The
recommendation is to use Low-ESL capacitors
connected with short traces to minimize the PCB
trace loop inductance.
- The
recommendation is to verify each of the power rail
pins has a decoupling capacitor and each of the
supply rail group has a bulk capacitor.
- Voltage
rating of the capacitors used (> twice the
worst-case applied voltage is a commonly used
guideline).
Additional
- In case
difference is observed between the EVM and the PDN
application note on the capacitor number recommendation and
value, the recommendation is to consider the recommendations
in the PDN application note
- While optimizing
the capacitors, the recommendation is to perform static and
dynamic PDN analysis to verify that the Reff, Cap LL, and
Impedance targets are met
- In some
situations, the EVM uses 3-terminal capacitors, due to low
inductance packaging. Make sure the 3-terminal capacitors
connections are not implemented as an in-line or filter
component
- The
recommendation is to show the connections of the capacitor
near to the relevant pin for ease of placement and
routing