ATXMEGA64A1 datasheet(21/99 Pages) ATMEL

21 / 99 page

8067I–AVR–04/09

XMEGA A1

10.3.3

32.768 kHz Crystal Oscillator

The 32.768 kHz Crystal Oscillator is a low power driver for an external watch crystal. It can be

used as system clock source or as asynchronous clock source for the Real Time Counter.

10.3.4

0.4 - 16 MHz Crystal Oscillator

The 0.4 - 16 MHz Crystal Oscillator is a driver intended for driving both external resonators and

crystals ranging from 400 kHz to 16 MHz.

10.3.5

2 MHz Run-time Calibrated Internal Oscillator

The 2 MHz Run-time Calibrated Internal Oscillator is a high frequency oscillator. It is calibrated

during productionn to provide a default frequency which is close to its nominal frequency. The

oscillator can use the 32 kHz Calibrated Internal Oscillator or the 32 kHz Crystal Oscillator as a

source for calibrating the frequency run-time to compensate for temperature and voltage drift

hereby optimizing the accuracy of the oscillator.

10.3.6

32 MHz Run-time Calibrated Internal Oscillator

The 32 MHz Run-time Calibrated Internal Oscillator is a high frequency oscillator. It is calibrated

during production to provide a default frequency which is close to its nominal frequency. The

oscillator can use the 32 kHz Calibrated Internal Oscillator or the 32 kHz Crystal Oscillator as a

source for calibrating the frequency run-time to compensate for temperature and voltage drift

hereby optimizing the accuracy of the oscillator.

10.3.7

External Clock input

The external clock input gives the possibility to connect a clock from an external source.

10.3.8

PLL with Multiplication factor 1 - 31x

The PLL provides the possibility of multiplying a frequency by any number from 1 to 31. In com-

bination with the prescalers, this gives a wide range of output frequencies from all clock sources.

ATXMEGA64A1 датащи(PDF) 21 Page - ATMEL Corporation