AVR® Microcontroller Hardware Design Considerations

1 Abbreviations

2.1 Digital Supply

2.2 Analog Supply

3 Connection of RESET Pin on AVR Devices

3.1 External RESET Switch

4 Connecting Programmer/Debugger Lines

4.1 SPI Programming Interface

4.2 JTAG Interface

4.3 PDI Interface

4.4 TPI Interface

4.5 UPDI Interface

5 Using Crystal and Ceramic Resonators

5.1 Selecting the Clock Source in the AVR MCU

5.2 About Crystals and Ceramic Resonators

5.3 Recommended Capacitor Values

5.4 Unbalanced External Capacitors

5.5 RTC Crystals

6 Unused XTAL Pins

7 Example Layout of ATxmega32A4 and ATmega324PB Devices

8 Revision History

The Microchip Web Site

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Microchip Devices Code Protection Feature

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