Texas Instruments Development Kit for TM4C129x,Tiva™ ARM® Cortex™ -M4 Microcontroller DK-TM4C129X DK-TM4C129X 데이터 시트
제품 코드
DK-TM4C129X
Figure 5-4. Power Architecture
Analog Circuits
I/O Buffers
LDO Voltage
Regulator
Internal
Logic and PLL
GND
GNDA
GNDA
VDDA
VDDA
VDDC
VDDC
+3.3V
GND
GND
GND
VDD
VDD
+3.3V
Note:
The V
DDA
voltage source is typically connected to a filtered voltage source or regulator.
5.2.5
Clock Control
The system control module determines the control of clocks in this part.
5.2.5.1
Fundamental Clock Sources
There are multiple clock sources for use in the microcontroller. The Run and Sleep Mode
Configuration Register (RSCLKCFG) can be used to configure the required clock source for the
device after Power-On Reset, as well as the system clock divisor encodings. The available clock
sources are as follows:
Configuration Register (RSCLKCFG) can be used to configure the required clock source for the
device after Power-On Reset, as well as the system clock divisor encodings. The available clock
sources are as follows:
■ Precision Internal Oscillator (PIOSC). The precision internal oscillator is an on-chip clock
source that the microcontroller uses during and following POR. It is the clock source in effect at
the start of reset vector fetch and the start of code application execution. It does not require the
use of any external components and provides a clock that is 16 MHz ±3% across temperature.
The PIOSC allows for a reduced system cost in applications that require an accurate enough
clock source. If the main oscillator is required, software must enable the main oscillator following
reset and allow the main oscillator to stabilize before changing the clock reference. If the
Hibernation Module clock source is a 32.768-kHz oscillator, the precision internal oscillator can
be trimmed by software based on a reference clock for increased accuracy. Regardless of
whether or not the PIOSC is the source for the system clock, the PIOSC can be configured to
the start of reset vector fetch and the start of code application execution. It does not require the
use of any external components and provides a clock that is 16 MHz ±3% across temperature.
The PIOSC allows for a reduced system cost in applications that require an accurate enough
clock source. If the main oscillator is required, software must enable the main oscillator following
reset and allow the main oscillator to stabilize before changing the clock reference. If the
Hibernation Module clock source is a 32.768-kHz oscillator, the precision internal oscillator can
be trimmed by software based on a reference clock for increased accuracy. Regardless of
whether or not the PIOSC is the source for the system clock, the PIOSC can be configured to
December 13, 2013
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Texas Instruments-Advance Information
System Control