Datasheet

1103
SAM9X25 [DATASHEET]
11054E–ATARM–10-Mar-2014
46.14 POR Characteristics
A general presentation of Power-On-Reset (POR) characteristics is provided in Figure 46-5.
Figure 46-5. General Presentation of POR Behavior
When a very slow (versus t
RES
) supply rising slope is applied on POR VDD pin, the reset time becomes negligible and the
reset signal is released when V
DD
rises higher than V
th+
.
When a very fast (versus
t
RES
) supply rising slope is applied on POR VDD pin, the voltage threshold becomes negligible
and the reset signal is released after
t
RES
time. It is the smallest possible reset time.
46.14.1 Core Power Supply POR Characteristics
46.14.2 Backup Power Supply POR Characteristics
Dynamic
t
res
NRST
VDD
V
th+
V
th
-
Vop
Static
Vnop
Table 46-28. Core Power Supply POR Characteristics
Symbol Parameter Conditions Min Typ Max Unit
V
th+
Threshold Voltage Rising Minimum Slope of +2.0V/30ms 0.5 0.7 0.89 V
V
th-
Threshold Voltage Falling Minimum Slope of +2.0V/30ms 0.4 0.6 0.85 V
t
RES
Reset Time 30 70 130 µs
I
DD
Current consumption After t
RES
37µA
Table 46-29. Backup Power Supply POR Characteristics
Symbol Parameter Conditions Min Typ Max Unit
V
th+
Threshold Voltage Rising Minimum Slope of +2.0V/30ms 1.42 4.52 1.62 V
V
th-
Threshold Voltage Falling Minimum Slope of +2.0V/30ms 1.35 1.45 1.55 V
t
RES
Reset Time
V
DDBU
is 3.3V 30 80 220
µs
V
DDBU
is 1.8V 40 100 330
I
DD
Current consumption After t
RES
68.5µA