STM690A/692A/703/704/802/805/817/818/819
Figure 13. Power-fail comparator waveform (STM817/818/819)
VCC
VRST
VSO (or 2.4V)
PFO
(STM817/819)
PFO follows PFI
RST
RST to ECON Delay (STM818)
ECON (STM818)
Operation
trec
PFO follows PFI
AI08804a
Figure 14. Power-fail comparator waveform (STM690A/692A/703/704/802/805)
VCC
VRST
2.4V (or VSO)
PFO
PFO follows PFI
trec
PFO follows PFI
RST
AI08832a
2.10
Using a SuperCap™ as a backup power source
SuperCaps™ are capacitors with extremely high capacitance values (e.g., 0.47 F) for their
size. Figure 15 shows how to use a SuperCap as a backup power source. The SuperCap
may be connected through a diode to the 5 V supply. Since VBAT can exceed VCC while VCC
is above the reset threshold, there are no special precautions for using these supervisors
with a SuperCap.
Doc ID 10522 Rev 10
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