LM3S3768 Luminary Micro, Inc, LM3S3768 Datasheet - Page 71

• Manufacturer Part Number: LM3S3768
• Description: Lm3s3768 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

Figure 6-2. Main Clock Tree
Note:
6.1.5.2
June 02, 2008
The figure above shows all features available on all Stellaris® DustDevil-class devices.
a. Control provided by RCC register bit/field.
b. Control provided by RCC register bit/field or RCC2 register bit/field, if overridden with RCC2 register bit USERCC2.
c. Control provided by RCC2 register bit/field.
d. Also may be controlled by DSLPCLKCFG when in deep sleep mode.
MOSCDIS
Main OSC
IOSCDIS
(12 MHz)
(30 kHz)
Internal
Internal
Crystal Configuration for the Main Oscillator (MOSC)
The main oscillator supports the use of a select number of crystals. If the main oscillator is used by
the PLL as a reference clock, the supported range of crystals is 3.579545 to 16.384 MHz, otherwise,
the range of supported crystals is 1 to 16.384 MHz.
The XTAL bit in the RCC register (see page 85) describes the available crystal choices and default
programming values.
OSC
OSC
a
a
(32.768 kHz)
Hibernation
Module
÷ 4
OSCSRC
USBPWRDN
(400 MHz)
(240 MHz)
PWRDN
XTAL
XTAL
PLL
PLL
b,d
a
a
b
c
Preliminary
BYPASS
÷ 25
÷ 4
b,d
PWMDW
SYSDIV
b,d
a
USEPWMDIV
USESYSDIV
PWRDN
LM3S3768 Microcontroller
a,d
a
USB Clock
PWM Clock
System Clock
ADC Clock
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