LM3S8971 Luminary Micro, Inc, LM3S8971 Datasheet - Page 566

• Manufacturer Part Number: LM3S8971
• Description: Lm3s8971 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

Electrical Characteristics
23.2.6
566
Table 23-21. External XTLP Oscillator Characteristics
a. IEEE 802.3 frequency tolerance ±50 ppm.
b. IEEE 802.3 frequency tolerance ±50 ppm.
Hibernation Module
The Hibernation Module requires special system implementation considerations since it is intended
to power-down all other sections of its host device. The system power-supply distribution and
interfaces to the device must be driven to 0 V
regulator controlled by HIB.
The external voltage regulators controlled by HIB must have a settling time of 250 μs or less.
Table 23-22. Hibernation Module AC Characteristics
a. This parameter is highly sensitive to PCB layout and trace lengths, which may make this parameter time longer. Care
Figure 23-3. Hibernation Module Timing
XTLN Input Low Voltage
Parameter No
32.768 KHz
(internal)
Parameter Name
XTLP Frequency
must be taken in PCB design to minimize trace lengths and RLC (resistance, inductance, capacitance).
XTLP Duty Cycle
Rise/Fall Time
Absolute Jitter
XTLP Period
/WAKE
H1
H2
H3
H4
H5
H6
H7
/HIB
t
t
t
HIB_REG_WRITE
HIB_TO_VDD
t
WAKE_ASSERT
XOSC_SETTLE
Parameter
t
b
WAKETOHIB
t
t
HIB_HIGH
HIB_LOW
a
H1
Symbol
XTLN
XTLP
T
XTLP
T
clkper
r
, T
DC
f
f
ILV
Internal 32.768 KHz clock reference rising edge to /HIB asserted
Internal 32.768 KHz clock reference rising edge to /HIB deasserted
/WAKE assertion time
/WAKE assert to /HIB desassert
XOSC settling time
Time for a write to non-volatile registers in HIB module to complete
HIB deassert to VDD and VDD25 at minimum operational level
Min
40
40
-
-
-
-
-
Nom
25.0
40
-
-
-
-
Preliminary
Max
0.8
4.0
0.1
60
60
-
-
a
Unit
ns
ns
%
-
-
-
DC
Parameter Name
or powered down with the same external voltage
H3
H4
H2
Min
62
62
20
92
-
-
-
Nom
200
July 26, 2008
30
-
-
-
-
-
Max
124
250
-
-
-
-
-
Unit
ms
μs
μs
μs
μs
μs
μs