ATXMEGA8E5 datasheet(27/153 Pages) MICROCHIP

27 / 153 page

 2018 Microchip Technology Inc.

Data Sheet Complete

DS40002059A-page 27

ATxmega32E5/16E5/8E5

Figure 11-1. The Clock System, Clock Sources, and Clock Distribution

11.3 Clock Sources

The clock sources are divided in two main groups: internal oscillators and external clock sources. Most of the clock sources

can be directly enabled and disabled from software, while others are automatically enabled or disabled, depending on

peripheral settings. After reset, the device starts up running from the 2MHz output of the 8MHz internal oscillator. The other

clock sources, DFLL and PLL, are turned off by default.

The internal oscillators do not require any external components to run. For details on characteristics and accuracy of the

internal oscillators, refer to the device datasheet.

11.3.1

32kHz Ultra Low Power Internal Oscillator

This oscillator provides an approximate 32kHz clock. The 32kHz ultra low power (ULP) internal oscillator is a very low

power clock source, and it is not designed for high accuracy. The oscillator employs a built-in prescaler that provides a

1kHz output. The oscillator is automatically enabled/disabled when it is used as clock source for any part of the device. This

oscillator can be selected as the clock source for the RTC.

Real Time

Counter

Peripherals

RAM

AVR CPU

Non-Volatile

Memory

Watchdog

Timer

Brown-out

Detector

System Clock Prescalers

System Clock Multiplexer

(SCLKSEL)

32 kHz

Int. ULP

32.768 kHz

Int. OSC

32.768 kHz

TOSC

8MHz

Int. Osc

32 MHz

Int. Osc

0.4 – 16 MHz

XTAL

PLL

clkSYS

clkRTC

clkPER2

clkPER

clkCPU

clkPER4

XOSCSEL

RTCSRC

PLLSRC

ATXMEGA8E5 Datasheet(PDF) 27 Page - Microchip Technology

ATXMEGA8E5 Datasheet(HTML) 27 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL