LM3S1621 Datasheet, PDF (892/947 Pages) Texas Instruments – ARM and Thumb are registered trademarks and Cortex is a trademark

Electrical Characteristics
21.8.2
21.8.3
Table 21-8 on page 892 shows the actual frequency of the PLL based on the crystal frequency used
(defined by the XTAL field in the RCC register).
Table 21-8. Actual PLL Frequency
XTAL
0x04
0x05
0x06
0x07
0x08
0x09
0x0A
0x0B
0x0C
0x0D
0x0E
0x0F
0x10
0x11
0x12
0x13
0x14
0x15
0x16
Crystal Frequency (MHz)
3.5795
3.6864
4.0
4.096
4.9152
5.0
5.12
6.0
6.144
7.3728
8.0
8.192
10.0
12.0
12.288
13.56
14.318
16.0
16.384
PLL Frequency (MHz)
400.904
398.1312
400
401.408
398.1312
400
399.36
400
399.36
398.1312
400
398.6773333
400
400
401.408
397.76
400.90904
400
404.1386667
Error
0.0023%
0.0047%
-
0.0035%
0.0047%
-
0.0016%
-
0.0016%
0.0047%
-
0.0033%
-
-
0.0035%
0.0056%
0.0023%
-
0.010%
PIOSC Specifications
Table 21-9. PIOSC Clock Characteristics
Parameter
F_PIOSC25
F_PIOSCT
F_PIOSCUCAL
Parameter Name
Min
Internal 16-MHz precision oscillator frequency variance, -
factory calibrated at 25 °C
Internal 16-MHz precision oscillator frequency variance, -
factory calibrated at 25 °C, across specified temperature
range
Internal 16-MHz precision oscillator frequency variance, -
user calibrated at a chosen temperature
Nom
±0.25%
-
±0.25%
Max
Unit
±1%
-
±3%
-
±1%
-
Internal 30-kHz Oscillator Specifications
Table 21-10. 30-kHz Clock Characteristics
Parameter
Parameter Name
Min
F_IOSC30KHZ
Internal 30-KHz oscillator frequency
15
Nom
30
Max
45
Unit
KHz
892
January 21, 2012
Texas Instruments-Production Data