RAK4260 Evaluation Board Datasheet

Overview

Description

RAK4260 Evaluation Board is designed to give you a quick start to explore the LoRa/LPWAN world. The board measures 30 x 60 mm and supports USB power supply, 3.7 V LiPo battery and 5 V solar charging.

The board itself has the RAK4260 as its core, which is a module that utilizes ATSAMR34J18B SiP. The high level of integration allows for outstanding performance: Lora TX Power of up to 20 dBm.

The board complies with LoRaWAN 1.0.2 specification, and it also supports LoRa P2P Point-to-Point communication. The low-power, long-range LoRa communication capabilities of the board make it suitable for a variety of applications in the IoT field such as home automation, sensor networks, building automation, and personal area networks applications such as health/fitness sensors and monitors.

Features

• 32-bit ARM Cortex M0+ MCU and SX1276 LoRa transceiver
• RAK4260 @ 32 MHz with 3.3 V logic/power
• 32.768 kHz crystal for clock generation & RTC
• 256 KB flash memory + 40 KB of RAM
• Hardware Serial, hardware I2C, hardware SPI support
• PWM outputs on all pins
• Programmable built-in LED for customized applications

Specifications

Overview

The RAK4260 Evaluation Board front view (top) and back view are shown in Figure 1.

Figure 1: RAK4260 Evaluation Board front and back view

Hardware

The hardware specification is categorized into five parts. It covers the interfaces, pin definitions and its corresponding functions. Also, it includes the RF requirements, electrical and mechanical parameters of the RAK4260 Evaluation Board.

Interfaces

Figure 2 shows an overview of interfaces found on the RAK4260 Evaluation Board.

Figure 1: RAK4260 Evaluation Board Interface Overview

SWD Programming Interface

When programming via a DAPLink tool, it is required to have all of the following four (4) pins connected to your DAPLink tool:

1. 3V3
2. SWDIO
3. SWCLK
4. GND

NOTE

For the aforementioned reason, it is best you leave these exposed for programming purposes and not to remap them as GPIOs.

Flash the Firmware Using DAPLink and RAKDAP1

Refer to section Flash the Firmware Using DAPLink and RAKDAP1.

RF Interface

The RF pin of the RAK4260 Evaluation Board is connected to an external LoRa Antenna through a standard iPEX antenna connector.

warning

Before powering the RAK4260 Evaluation Board, you should install the LoRa antenna first. Not doing so might damage the board.

USB Interface

The Micro-B USB connector is compliant with the USB2.0 specification. The pin definition of the USB interface is shown below:

Pin Number	**Pin Name	Description
1	USB_VBUS	(+5 V) USB Bus Voltage
2	USB_DM	USB Bus D+ positive pin
3	USB_DP	USB Bus D- negative pin
4	NC	Not connected
5	GND	Ground

Figure 1: RAK4260 Micro-B USB connector

The USB data bus is connected to a USB-SERIAL CH-340 chip. The CH-340 is basically a USB bus convert chip that allows the USB to be converted to serial interface and serial interface pins converted to USB.

Pin Definition

The following tables below shows the pin definitions of the RAK4260 Evaluation Board:

J10, J11, J12 2.54 mm header

On the RAK4260 Evaluation Board, there are three 2.54 mm pitch headers used for IO extension. Some data bus and signal from the MCU module are also connected to these headers, such as I2C, UART, ADC, etc.

J10 pin definition

Pin Number	**Pin Name	Description	Microcontroller pin
1	BOOT0	Boot for ST MCU
2	VDD	Power supply generated by CPU module
3	TX1	UART3 TX pin	PA19
4	RX1	UART3 RX pin	PA18

J11 pin definition

Pin Number	Pin Name	Description	Microcontroller pin
1	AIN0	ADC input signal	PA08
2	IO1	General purpose IO	PB22
3	IO2	Power switch control of 3V3_S	PA15
4	GND	Ground

NOTE

3V3_S is another 3.3 V power supply that can be controlled on/off by MCU. Set IO2=0 when the sensor is not in use to save power.

J12 pin definition

Pin Number	Pin Name	Description	Microcontroller pin
1	GND	Ground
2	I2C1_SCL	I2C clock	PA17
3	I2C1_SDA	I2C data	PA16
4	VDD	Power supply generated by CPU module

IO Module Connector pin definition

Figure 1: RAK4260 IO Module Connector

Pin Number	Pin Name	Description	Microcontroller pin
1	VBAT	Li-Ion Battery positive pin
2	VBAT	Li-Ion Battery positive pin
3	GND	Ground
4	GND	Ground
5	3V3	3.3 V power supply
6	3V3_S	3.3 V power supply can be shutdown by CPU module
7	USB+	USB Bus D+ positive pin	PA25
8	USB-	USB Bus D- negative pin	PA24
9	VBUS	5 V USB Bus Voltage
10	SW1	Switch signal for custom use
11	UART1_TX	UART1 TX signal	PA04
12	UART1_RX	UART1 RX signal	PA05
13	RESET	Connected to the reset switch for MCU reset
14	LED1	Red LED for battery charge indicator
15	LED2	Green LED for custom use	PA27
16	LED3	BLue LED for custom use	PA06
17	VDD	Power supply generated by CPU module. Used to power sensor board if the MCU IO level is not 3.3 V
18	VDD	Power supply generated by CPU module. Used to power sensor board if the MCU IO level is not 3.3 V
19	I2C1_SDA	I2C Data Signal	PA17
20	I2C1_SCL	I2C clock signal	PA16
21	AIN0	Analog Input for ADC	PA08
22	AIN1	Analog Input for ADC	PA09
23	BOOT0	Boot for ST MCU
24	NC	Not connected
25	SPI_CS	SPI chip select signal	PA22
26	SPI_CLK	SPI clock signal	PB23
27	SPI_MISO	SPI MISO signal	PB02
28	SPI_MOSI	SPI MISO signal	PA23
29	IO1	General Purpose IO	PB22
30	IO2	Power switch control of 3V3_S	PA15
31	IO3	General Purpose IO	PA14
32	IO4	General Purpose IO
33	TX1	UART3 TX pin	PA19
34	RX1	UART3 RX pin	PA18
35	I2C2_SDA	The second set of I2C data signal
36	I2C2_SCL	The second set of I2C clock signal
37	IO5	General Purpose IO
38	IO6	General Purpose IO
39	GND	Ground
40	GND	Ground

Sensor Module Connector Pin Definition

Figure 1: Sensor Module Connector

Slot A

Pin Number	Pin Name	Description	Microcontroller Pin
1	TX1	UART3 TX pin	PA19
2	GND	Ground
3	SPI_CS	SPI chip select signal	PA22
4	SPI_CLK	SPI clock signal	PB23
5	SPI_MISO	SPI MISO signal	PB02
6	SPI_MOSI	SPI MOSI signal	PA23
7	I2C1_SCL	I2C clock signal	PA17
8	I2C1_SDA	I2C data signal	PA16
9	VDD	Controlled by CPU module. Used to power sensor board if the MCU IO level is not 3.3 V
10	IO2	General Purpose IO	PA15
11	3V3_S	3.3 V power supply can be shutdown by CPU module
12	IO1	General Purpose IO	PB22
13	NC	Not connected
14	3V3_S	3.3 V power supply can be shutdown by CPU module
15	NC	Not connected
16	VDD	Controlled by CPU module. Used to power sensor board if the MCU IO level is not 3.3 V
17	NC	Not connected
18	NC	Not connected
19	NC	Not connected
20	NC	Not connected
21	NC	Not connected
22	NC	Not connected
23	GND	Ground
24	RX1	UART3 RX pin	PA18

Slot B

Pin Number	Pin Name	Description	Microcontroller Pin
1	NC	Not connected
2	GND	Ground
3	SPI_CS	SPI Chip Select Pin	PA22
4	SPI_CLK	SPI Clock signal	PB23
5	SPI_MISO	SPI MISO signal	PB02
6	SPI_MOSI	SPI MOSI signal	PA23
7	I2C1_SCL	I2C Clock signal	PA17
8	I2C1_SDA	I2C Data signal	PA16
9	VDD	Controlled by CPU module. Used to power sensor board if the MCU IO level is not 3.3 V
10	IO1	General Purpose IO	PB22
11	3V3_S	3.3 V power supply can be shutdown by CPU module
12	IO2	General Purpose IO	PA15
13	NC	Not connected
14	3V3_S	3.3 V power supply can be shutdown by CPU module
15	NC	Not connected
16	VDD	Controlled by CPU module. Used to power sensor board if the MCU IO level is not 3.3 V
17	NC	Not connected
18	NC	Not connected
19	NC	Not connected
20	NC	Not connected
21	NC	Not connected
22	NC	Not connected
23	GND	Ground
24	NC	Not connected

Slot C

Pin Number	Pin Name	Description	Microcontroller Pin
1	NC	Not connected
2	GND	Ground
3	SPI_CS	SPI Chip Select Pin	PA22
4	SPI_CLK	SPI Clock Pin	PB23
5	SPI_MISO	SPI MISO signal	PB02
6	SPI_MOSI	SPI MOSI signal	PA23
7	I2C1_SCL	I2C Clock signal	PA17
8	I2C1_SDA	I2C Data signal	PA16
9	VDD	Controlled by CPU module. Used to power sensor board if the MCU IO level is not 3.3 V
10	IO4	General Purpose IO
11	3V3_S	3.3 V power supply, can be shutdown by CPU module
12	IO5	General Purpose IO
13	NC	Not connected
14	3V3_S	3.3 V power supply, can be shutdown by CPU module
15	NC	Not connected
16	VDD	Controlled by CPU module. Used to power sensor board if the MCU IO level is not 3.3 V
17	NC	Not connected
18	NC	Not connected
19	NC	Not connected
20	NC	Not connected
21	NC	Not connected
22	NC	Not connected
23	GND	Ground
24	NC	Not connected

Slot D

Pin Number	Pin Name	Description	Microcontroller Pin
1	NC	Not connected
2	GND	Ground
3	SPI_CS	SPI Chip Select Pin	PA22
4	SPI_CLK	SPI Clock Pin	PB23
5	SPI_MISO	SPI MISO signal	PB02
6	SPI_MOSI	SPI MOSI signal	PA23
7	I2C1_SCL	I2C Clock signal	PA17
8	I2C1_SDA	I2C Data signal	PA16
9	VDD	Power supply generated by CPU module. Used to power sensor board if the MCU IO level is not 3.3 V
10	IO6	General Purpose IO
11	3V3_S	3.3 V power supply, can be shutdown by CPU module
12	IO5	General Purpose IO
13	NC	Not connected
14	3V3_S	3.3 V power supply, can be shutdown by CPU module
15	NC	Not connected
16	VDD	Power supply generated by CPU module. Used to power sensor board if the MCU IO level is not 3.3 V
17	NC	Not connected
18	NC	Not connected
19	NC	Not connected
20	NC	Not connected
21	NC	Not connected
22	NC	Not connected
23	GND	Ground
24	NC	Not connected

Battery Connector

The pin definition of the RAK4260 Evaluation Board Li-Ion battery connector is shown in the table below. The matching connector for the battery wires is an JST PHR-2 2 mm pitch female.

Pin	Pin Name	Description
1	GND	Ground
2	VBAT	Positive + pin of the battery

The full specification of the RAK4260 Evaluation Board battery is shown in the table below.

No.	Item	Specification
1	Charge Cut-off Voltage	4.2 V
2	Nominal Voltage	3.7 V
3	Discharge Cut-off Voltage	2.75 V
4	Typical Capacity	2650 mAh
5	Max Discharge Current	0.5 C at 25 ℃ to 45 ℃
6	PH Connector	2.0 mm pitch
7	Cable Length	110.0±3.0 mm
8	Cable Color	Red: VBAT, Black: GND

NOTE

The voltage of the Li-Ion battery must not exceed 4.3 V. When connecting the battery make sure the polarity is correct. Not all connectors are wired the same.

Solar Panel Connector

The pin definition of the RAK4260 Evaluation Board solar panel connector is shown in the table below. The matching connector for the solar panel wires is an JST ZHR-2 1.5 mm pitch female

Pin	Pin Name	Description
1	C0NN_5V	Positive + pin of solar panel
2	GND	GND

The full specification of the Solar Panel for the RAK4260 Evaluation Board is shown in the table below.

No.	Item	Specification
1	Nominal Voltage	5 V
2	Typical Current	80 mA
3	Size	Length: 60 mm, Width: 60 mm, Height: 2 mm
4	Connector	1.5 mm pitch
5	Cable Color	Red: C0NN_5V, Black: GND

NOTE

The output of the solar panel must not exceed 5.5 V. Otherwise, it may cause permanent damage to the board.

LEDs

Three LEDs are used to indicate the operating status. Below are the functions of the LEDs:

• 🔴 Red LED - connected to the charger chip to indicate the charger status. When the battery is charging, this red LED is on. When the battery is full, this LED is weak light or off.
• 🟢 Green LED - connected to the MCU module pin PA27.
• 🔵 Blue LED - connected to the MCU module pin PA06.

RESET Button

The reset push button is connected to the reset pin of the RAK4260. When pushed, it resets the MCU.

TCXO Power Pin Definition

The TCXO (Temperature compensated crystal oscillator) power pin is PB03.

RF Switch Pin Definition

BAND_SEL	TX/RX
PA13	RXTX

RF Switch control logic table

LoRa Mode	BAND_SEL	TX/RX	PA28
Shutdown	L	L	L
PA_BOOST	L	H	H
RFI_HF (RX)	H	L	H
RFO_HF	H	H	H

NOTE

PA28 is RF Switch VDD pin
H = High level
L = Low level

RF Requirements

Operating Frequencies

The RAK4260 Evaluation Board supports the following LoRa bands:

Region	Frequency (MHz)
Europe	EU868
North America	US915
Australia	AU915
Asia	AS923

Electrical Characteristics

Power Consumption

Conditions	Current	Unit
Leakage current	2	uA
Idle current (MCU and sensor in sleep mode)	10	uA
Working current (LoRa module transmitting)	130	mA

Absolute Maximum Ratings

Exposure to maximum rating conditions may affect device reliability.

Ratings	Maximum Value	Unit
VBUS power supply on USB port	-0.3 - 5.5	V
VBAT battery voltage	-0.3 - 4.3	V
C0NN_5V solar panel voltage	-0.3 - 5.5	V
IO connector	-0.3 - VDD+0.3	V
ESD	2000	V

Mechanical Characteristics

Board Dimensions

Figure 6 shows the actual dimensions of the RAK4260 Evaluation Board measured in millimeters (mm).

Figure 1: RAK4260 Evaluation Board dimensions

Schematic Diagram

Figure 1: RAK4260 WisDuo LPWAN Module Schematic Diagram

Certification

CE Certification

FCC Certification