The kit comprises a baseboard with a soldered SAMA5D27 SOM1 module. The module features a
SAMA5D27-D1G-CU SIP embedding a 1-Gbit DDR2 SDRAM. The SOM offers a reliable and costeffective embedded platform for building end products, as well as a small form factor, complemented by
many connectivity interfaces. The SOM is a fully-featured industrially-certified single board computer
designed for integration into customer applications.
The SOM module is a purpose-built small footprint hardware platform equipped with a wide array of highspeed connectivity engineered to support various applications such as IoT endpoints, wearables,
appliances or industrial equipment.
SAMA5D27 SOM1 Kit1
Product Overview
The SOM integrates a 1-Gbit DDR2 SDRAM, a QSPI memory and a 10/100 Mbps Ethernet controller.
128 GPIO pins are provided by the SOM for general use in the system. All GPIO pins are independent
and can be configured as inputs or outputs, with or without pull-up/pull-down resistors.
The baseboard features a wide range of peripherals, as well as a user interface and expansion options,
including two mikroBUS™ click interface headers to support over 300 MikroElektronika click boards™ and
one Pmod™ interface.
Table 2-1. Baseboard Features
Characteristics SpecificationsComponents
MemoryOne QSPI Flash (unmounted)Tested with Macronix MX25L25673GM2I-08G
Microchip SAM3U micro-controller with
embedded J-Link firmware
–
–
Power ON, Reset, Wakeup, User Free
10-pin male connector
6-pin female connector
2x8-pin female connector
CharacteristicSpecification
Ordering codeATSAMA5D27-SOM1-EK1
Board supply voltageUSB-powered
TemperatureOperating: 0°C to +70°C
Relative humidity0 to 90% (non-condensing)
Baseboard dimensions135 × 90 × 20 mm
RoHS statusCompliant
2.4 Power Sources
Two options are available to power up the baseboard:
•USB powering through the USB Micro-AB connector (J17 - default configuration)
•Powering through the USB Micro-AB connector on the J-Link-OB Embedded Debugger interface
(J10)
The two power sources can coexist. A priority mechanism manages the automatic switching between the
two. The priority source is J-Link (J10), the secondary source is the USB port (J17).
This section covers the specifications of the SAMA5D27 SOM1 Kit1 baseboard and provides a high-level
description of the baseboard's major components and interfaces. This document is not intended to
provide a detailed documentation about the processor or about any other component used on the
baseboard. It is expected that the user will refer to the appropriate documents of these devices to access
detailed information.
3.1 Baseboard Overview
The fully-featured SAMA5D27 SOM1 Kit1 baseboard integrates multiple peripherals and interface
connectors, as shown in the figure below.
Figure 3-1. SAMA5D27 SOM1 Kit1 Baseboard Overview
SAMA5D27 SOM1 Kit1
Baseboard Components
The following picture illustrates the kit block diagram.
The figure below shows the default jumper settings. Jumpers in red are configuration items and current
measurement points. The following table describes the functionality of the jumpers.
3.2.2 Power Supply Topology and Power Distribution
100k
0402
1%
R8
5
84
3
DMP2160
Q1B
1 2
J1
5
84
3
DMP2160
Q2B
0.1uF
50V
0402
C4
10k
0402
5%
R3
0.1uF
50V
0402
C9
2
71
6
DMP2160
Q2A
2
71
6
DMP2160
Q1A
100k
0402
1%
R12
0.1uF
50V
0402
C1
100k
0402
1%
R1
VBUS_JLINKVDD_MAIN_5V
VBUS_USBA
Shunt 2.54mm 1x2
CAUTION
3.2.2.1 Input Power Options
The board power source can come through either a USB connector (J10 or J17) connected to a PC or a
5V DC-USB power supply unit. These USB power sources are sufficient to supply the board in most
applications.
Important: In case of an external device connected through the USB-B port, it is
recommended to use the 5V DC-USB power supply unit as the main power source for the entire
system rather than a PC or a USB hub, which are limited to 500 mA typical.
The baseboard embeds a local power management stage comprising two sets of load switches,
respectively implemented by MOSFET DMP2160 and DC/DC converter MIC23451.
The following figure is a schematic of the power options.
Figure 3-5. Input Powering
SAMA5D27 SOM1 Kit1
Baseboard Components
Note: PC/USB-powered operation eliminates additional wires and batteries. It is the preferred mode of
operation for any project that requires only a 5V source at up to 500 mA.
Jumper J1 is used to perform MAIN_5V current measurements on the baseboard.
3.2.2.2 Power Supply Requirements and Restrictions
Detailed information on the device power supplies is provided in tables “SAMA5D2 Power Supplies” and
“Power Supply Connections” in the SAMA5D2 Series datasheet.
3.2.2.3 Power-up and Power-down Considerations
Power-up and power-down considerations are described in section “Power Considerations” of the
SAMA5D2 Series datasheet.
The power-up and power-down sequences provided in the SAMA5D2 Series datasheet must be
respected for reliable operation of the device. These are respected by the on-board MIC23451.
3.2.2.4 Power Management
The baseboard power management uses a MIC23451 PMIC, which is a triple synchronous buck regulator
with HyperLight Load® mode featuring a power good indicator. The triple DC-DC step down power
regulator delivers two outputs: 3.3V/2A and 1.8V/2A.
While the external power is being applied, the baseboard can be shut down by software and then woken
up by action on the PB2 push button, which activates the WKUP signal.
The figure below shows the power management scheme.
Figure 3-6. Baseboard Power Management
One PIO (PD8) is used to check the status of the main regulator.
Table 3-3. Power Good Signal
PIOMnemonicSignal Description
PD8BB_PWR_GOODHigh level = power is established
3.2.2.5 Supply Group Configuration
The main regulator provides the 3.3V for the SOM and all power supplies required by the baseboard:
The baseboard features a power source in order to permanently power the backup area of the SAMA5D2
device (refer to the SAMA5D2 Series datasheet). A super capacitor (C14) sustains such permanent
power to VDDBU when all system power sources are off.
Figure 3-8. VDDBU Powering Options
SAMA5D27 SOM1 Kit1
Baseboard Components
3.2.3 Shutdown Circuitry
On the baseboard, this circuitry is implemented but inhibited by default (R131 is not populated).
The SHDN signal, output of the shutdown controller, signals the shutdown request to the power supply.
This output signal is supplied by VDDBU that is present in Backup mode.
The shutdown controller manages the main power supply and is connected to the ENABLE input pin of
the DC/DC converter providing the main power supplies of the system.
•One reset push button (PB1). When pressed and released, the baseboard is reset.
•One wake-up push button (PB2) connected to the SAMA5D27 WKUP pin, used to exit the
processor from Backup mode.
•One power-on button (PB3).
Figure 3-10. System Push Buttons
•One user momentary push button (PB4) connected to PIO PA29, and optionally to PIOBU1.
The wake-up is available only if the shutdown controller is used (see figure Shutdown Controller).
Figure 3-11. User Push Button
3.2.5 Additional Memories
One additional memory, QSPI device U9, can be soldered on the baseboard. This QSPI Flash memory
uses the same PIOs as the SOM QSPI. Such configuration makes it possible to choose between two
bootable memories.
The figure below illustrates the QSPI memory implementation.
Figure 3-12. Optional QSPI Serial Data Flash on Baseboard
One jumper (J13) controls the selection (CS#) of the bootable memory components (QSPI) using a noninverting 3-state buffer.
Figure 3-13. CS Disable Boot
The rule of operation is:
•PB1 (RESET) pressed and J13 open = booting from QSPI on SOM
•PB1 (RESET) pressed and J13 closed = booting from QSPI on baseboard if fitted. The QSPI on
SOM is disabled.
Refer to the SAMA5D2 Series datasheet for more information on standard boot strategies and
sequencing.
SAMA5D27 SOM1 Kit1
Baseboard Components
3.2.6 Secure Digital Multimedia Card (SDMMC) Interface
The SD (Secure Digital) Card is a non-volatile memory card format used as a mass storage memory in
mobile devices.
3.2.6.1 Secure Digital Multimedia Card (SDMMC) Controller
The baseboard features two Secure Digital Multimedia Card (SDMMC) interfaces that support the
MultiMedia Card (e.MMC) Specification V4.41, the SD Memory Card Specification V3.0, and the SDIO
V3.0 specification. It is compliant with the SD Host Controller Standard V3.0 Specification.
•The SDMMC0 interface is connected to a standard SD card interface.
•The SDMMC1 interface is connected to a microSD card interface.
3.2.6.2 SDMMC0 Card Connector (J12)
A standard MMC/SD card connector, connected to SDMMC0, is mounted on the top side of the
baseboard. The SDMMC0 communication is based on a 12-pin interface (clock, command, write protect,
power switch and data (8)). A card detection switch is included.
The figure below illustrates the SDMMC0 interface implementation.
A microSD card connector, connected to SDMMC1, is mounted on the top side of the baseboard. The
SDMMC1 communication is based on a 6-pin interface (clock, command and four data). A card detection
switch is included. The microSD connector can be used to connect any microSD card for mass storage.
ATECC608A is a member of the CryptoAuthentication family of crypto engine authentication devices with
highly secure hardware-based key storage.
The ATECC608A features a flexible command set enabling use in many applications, including
network/IoT node protection, anti-counterfeiting, firmware or media protection, secure data storage and
user password checking.
The device (U11) is mounted in an 8-lead UDFN package.
For more information, refer to the ATECC608A datasheet on www.microchip.com.
Figure 3-18. CryptoAuthentication ATECC608
Table 3-8. ATECC608 PIO Signal Descriptions
PIOMnemonicSharedSignal Description
PD21TWD0SOM E2PROM
PD22TWCK0SOM E2PROM
™
TWI data
24AA02E48
TWI clock
24AA02E48
3.2.7 Communication Interfaces
This section describes the signals and connectors related to the ETH, USB and CAN communication
interfaces.
3.2.7.1 Ethernet 10/100 (GMAC) Port
The on-board SOM integrates a 10/100 Mbps Ethernet controller (KSZ8081RNA) allowing direct
connection to any 10/100 Mbps Ethernet-based Local Area Network, for full interaction with local servers
and wide area networks such as the Internet.
ETH signals from the SOM are connected to a RJ45 MagJack. Additionally, for monitoring and control
purposes, a LED functionality is carried on the RJ45 connector to indicate link status.