LM3S818 Luminary Micro, Inc, LM3S818 Datasheet - Page 375

• Manufacturer Part Number: LM3S818
• Description: Lm3s818 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

20.2
20.2.1
20.2.2
February 6, 2007
AC Characteristics
Load Conditions
Unless otherwise specified, the following conditions are true for all timing measurements. Timing
measurements are for 4-mA drive strength.
Figure 20-1. Load Conditions
Clocks
Table 20-6. Phase Locked Loop (PLL) Characteristics
a. The exact value is determined by the crystal value programmed into the XTAL field of the Run-Mode Clock
b. PLL frequency is automatically calculated by the hardware based on the XTAL field of the RCC register.
Table 20-7. Clock Characteristics
f
f
f
T
f
f
t
f
f
REF_CRYSTAL
REF_EXT
PLL
IOSC
MOSC
MOSC_PER
REF_CRYSTAL_BYPASS
REF_EXT_BYPASS
READY
Configuration (RCC) register (see page 62).
Parameter
Parameter
Parameter Name
Internal oscillator
frequency
Main oscillator frequency
Main oscillator period
Crystal reference using the
main oscillator (PLL in
BYPASS mode)
External clock reference
(PLL in BYPASS mode)
Parameter Name
Crystal reference
External clock reference
PLL frequency
PLL lock time
pin
Preliminary
b
a
a
a
a
GND
3.579545
3.579545
C
Min
125
Min
L
7
1
1
0
-
-
= 50 pF
Nom
Nom
200
15
-
-
-
-
-
-
-
LM3S818 Data Sheet
8.192
8.192
1000
Max
Max
0.5
22
50
8
8
-
MHz
MHz
MHz
MHz
Unit
MHz
MHz
MHz
Unit
ms
ns
375