47.1 Introduction
This chapter describes a common checklist which should be used when starting and reviewing the schematics for a SAM L22 design. This chapter illustrates the recommended power supply connections, how to connect external analog references, programmer, debugger, oscillator and crystal.
If the device is operating in an environment with much electromagnetic noise, it must be protected from this noise to ensure reliable operation. In addition to following best practice EMC design guidelines, the recommendations listed in the schematic checklist sections must be followed. In particular, placing decoupling capacitors very close to the power pins, an RC-filter on the RESET pin, and a pull-up resistor on the SWCLK pin is critical for reliable operations.
It is also relevant to eliminate or attenuate noise in order to avoid that it reaches supply pins, I/O pins, and crystals.
Refer to the "EMI, EMC, EFT, and ESD Circuit Design Consideration for 32-bit Microcontrollers" guide ovailabe for download at he Microchip web site, www.microchip.com/.