SAMC21 datasheet(12/46 Pages) ATMEL

12 / 46 page

Hardware Users Guide

4.1.

Power Distribution

SAM C21 Xplained Pro has two power sources as described in Power Sources. Figure 4-1 shows a block

diagram of the power supply circuitry. The kit can be powered from the EDBG USB and an external 5.0V

source. The kit will automatically select which source to draw power from.

The EDBG controls an on-board power switch to the ATSAMC21J18A, the on-board peripherals, and

extension connectors. When the kit is powered up, the EDBG reads the ID chip information from all

connected Xplained Pro extension boards and checks that they are compatible with the voltage selected

by the power selection jumper. If the selected voltage is within the connected extensions ranges the

switch will open. If not, the EDBG power LED will blink rapidly and the switch will stay closed resulting in

no power provided to the ATSAMC21J18A, on-board peripherals, and connectors.

Caution: As the SAM C21 Xplained Pro can be powered by 5.0V care must be taken not to

connect any Xplained Pro extensions that does not support this voltage, doing so may result in

permanent damage. Check the respective extension kit's user guide to see which voltages are

acceptable.

Info: The EDBG only reads the ID information and controls the power switch when the kit is

powered up. This mechanism does not check hot-plugging of extension boards.

Figure 4-1. Power Supply Block Diagram

External 5V input

EDBG

SAMC21J18

Regulator 3.3V

Power Select

(Jumper)

EDBG USB

Auto mux

VCC_P3V3

Peripherals

VCC_TARGET

VCC_MCU

Power Switch

Jumper

Regulator 3.3V

Power source

Power switch

Power converter

Power consumer

Atmel SAM C21 Xplained Pro [USER GUIDE]

Atmel-42460D-SAM-C21-Xplained-Pro_User Guide-08/2016

SAMC21 bảng dữ liệu(PDF) 12 Page - ATMEL Corporation