atxmega128a4-mu ATMEL Corporation, atxmega128a4-mu Datasheet - Page 15

• Manufacturer Part Number: atxmega128a4-mu
• Description: Atxmega16a4 8/16-bit Avr Xmega Microcontroller
• Manufacturer: ATMEL Corporation

10.3
10.3.1
10.3.2
10.3.3
10.3.4
10.3.5
10.3.6
10.3.7
10.3.8
8069A–AVR–02/08
Clock Options
32 kHz Ultra Low Power Internal Oscillator
32 kHz Calibrated Internal Oscillator
32 kHz Crystal Oscillator
0.4 - 16 MHz Crystal Oscillator
2 MHz Run-time Calibrated Internal Oscillator
32 MHz Run-time Calibrated Internal Oscillator
External Clock input
PLL with Multiplication factor 2 - 31x
The 32 kHz Ultra Low Power (ULP) Internal Oscillator is a very low power consumption clock
source based on internal components only. As it is intended mainly for system functions, it
should not be used when an accurate clock is required.
Compared to the internal ULP oscillator, the 32 kHz Calibrated Internal Oscillator is a high accu-
racy clock source based on internal components only.
The 32 kHz Crystal Oscillator is a low power driver for an external watch crystal.
The 0.4 - 16 MHz Crystal Oscillator is a driver intended both for driving resonators and crystals
from 400 kHz to 16 MHz.
The 2 MHz Run-time Calibrated Internal Oscillator is a high frequency oscillator based on inter-
nal components only. The oscillator can use the 32 kHz Calibrated Internal Oscillator or the 32
kHz Crystal Oscillator to calibrate the frequency run-time to compensate for temperature and
voltage drift, optimizing the accuracy of the oscillator.
The 32 MHz Run-time Calibrated Internal Oscillator is a high frequency oscillator based on inter-
nal components only. The oscillator can use the 32 kHz Calibrated Internal Oscillator or the 32
kHz Crystal Oscillator to calibrate the frequency run-time to compensate for temperature and
voltage drift, optimizing the accuracy of the oscillator.
The external clock input gives the possibility to connect to a clock from an external source.
The PLL provides the possibility of multiplying a frequency with any real number from 2 to 31. In
combination with some prescalers, this gives a numerous number of clock frequency options to
use.
ATxmega A4
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