General
Review and verify the following for
the custom schematic design:
- Reviewed above "Common checklist for all sections" section of the
user's guide
- Connection of always ON
(discrete, LDO) supplies for VDD_RTC and VDDS_RTC
- Connection of the combined PG
output of VDD_RTC and VDDS_RTC supplies to RTC_PORz input
- VDD_RTC and VDDS_RTC, supply
slew
- Addition of 22pF glitch
filter near to RTC_PORz input
- Slew of the discrete LDOs PG
output connected to RTC_PORz input
- Sequencing of the VDD_RTC
supply with respect to VDD_CORE
Schematic Review
Follow the below list for the custom schematic design:
- Use of always ON discrete LDO
supplies for VDD_RTC and VDDS_RTC
- Supply outputs are within the
ROC as per the processor-specific data sheet
- VDD_RTC supply ramps before
VDD_CORE
- VDD_RTC and VDDS_RTC supply
slew rate follows the data sheet specifications
- Discrete LDOs of PG outputs
for VDD_RTC and VDDS_RTC connected together
- Connection of PG output of
discrete LDOs to RTC_PORz input
Additional
- Note the use of diode at the input of discrete LDO input to sequence the VDD_RTC
supply