RAK4200 WisDuo LPWAN Module Datasheet

Overview

Description

RAK4200 WisDuo LPWAN Module includes an STM32L071 MCU and an SX1276 LoRa chip. It has Ultra-Low Power Consumption of 9.40 uA (down to 1.08 μA @ 2.0 V) in sleep mode and high LoRa output power up to 19 dBm max in work mode.

The module complies with LoRaWAN 1.0.2 specification. It also supports LoRa P2P Point-to-Point communications. The module is suitable for various applications that require long-range data acquisition and low power consumption.

Features

• LoRa module for Smart City, Smart Agriculture, Smart Industry
• Compact Form Factor: 15 x 15.5 x 2.5 mm
• 20 Pin Stamp Pad for PCB SMT mounting
• I/O ports: UART/I2C/GPIO/ADC
• Temperature range: -40° C to +85° C
• Supply voltage: 2.0 ~ 3.6 V
• Frequency range: 863–870 MHz (EU) / 902–928 MHz (US), ISM and SRD systems
• Low-Power Wireless Systems with 7.8 kHz to 500 kHz Bandwidth
• Ultra-Low Power Consumption of 9.40 μA (down to 1.08 μA @ 2.0 V) in sleep mode
• Core: ARM 32-bit Cortex – M0+ with MPU
• Up to 128 KB flash memory with ECC
• 20 KB RAM
• 6 KB of data EEPROM with ECC

Specifications

Overview

The overview covers the RAK4200 WisDuo board overview where the front and back views are presented. It includes also the block diagram that shows the external interfaces of the RAK4200 WisDuo.

Board Overview

Figure 7425: RAK4200 WisDuo LPWAN Module Front and Back View

Block Diagram

Figure 7426: RAK4200 WisDuo Block Diagram

Hardware

The hardware specification is categorized into five parts. It covers the pinouts and the corresponding functions and diagrams of the board. It also presents the parameters and its standard values in terms of electrical and mechanical.

Pin Definition

Figure 7427: Pinout for RAK4200

warning

When using RF pin for antenna and not the IPEX connector variant, there are design considerations to make sure optimum RF performance.

• RF trace must be away from interference (switching node of DC-DC supply, high current/voltage pulses from controllers of inductive load like motor, signal generators, etc.)
• RF trace must have 50 Ohms impedance. It is advisable to use an impedance simulation software tool to achieve this requirement.
• If using an external antenna connector, make it close to the RF pin.
• Ground plane optimization is critical on certain antenna types like monopole.
• GND trace used for RF path return must be directly connected to the GND plane and not be treated as thermal relief.
• It is recommended for the RF trace to be routed in a curve and not in a sharp 90 degrees.

In addition, with a commitment to making IoT easy, RAK offers a dedicated service for Antenna RF Design which includes PCB design, tuning, matching, and RF testing.

Pin	Name	I/O	Description
1	UART2_RX	I	UART2 Interface (AT Commands) (STM32L071 PA3)
2	UART2_TX	O	UART2 Interface (AT Commands) (STM32L071 PA2)
3	UART2_DE	I/O	GPIO (STM32L071 PA1)
4	UART1_TX	O	UART1 Interface (AT Commands and FW Update) (STM32L071 PA9)
5	UART1_RX	I	UART1 Interface (AT Commands and FW Update) (STM32L071 PA10)
6	UART1_DE	I/O	General GPIO or UART(Reserved) (STM32L071 PA12)
7	SWDIO	I/O	Programming (STM32L071 PA13)
8	SWCLK	I/O	Programming (STM32L071 PA14)
9	I2C_SCL	I/O	I2C interface (STM32L071 PB6)
10	I2C_SDA	I/O	I2C interface (STM32L071 PB7)
11	GND	-	Ground
12	RF	I/O	RF port (only available on RAK4200 No-IPEX connector variant)
13	GND	-	Ground
14	GND	-	Ground
15	SPI_CLK	I/O	Reserved PA5
16	SPI_MISO	I/O	Reserved PA6
17	SPI_MOSI	I/O	Reserved PA7
18	MCU_NRST	I/O	MCU reset (STM32L071 NRST)
19	GND	-	Ground
20	VDD	-	DC 3V3

LoRa Transceiver IC Connection to RAK4200 Internal STM32

LoRa IC Pin	STM32 GPIO
DIO0	PB0
DIO1	PB1
DIO2	PB5
DIO3	PB4
SPI1_CLK	PA5
SPI1_MISO	PA6
SPI1_MOSI	PA7
SPI1_NSS	PA4
NRESET	PA0
VCTL1	PA11
VCTL2	PA8

LoRa Transceiver Mode

LoRa Mode	VCTL1 GPIO	VCTL2 GPIO
TX mode	H	L
RX mode	L	H

:::tipLogic Level H level (1.8 - 5.0 V)
L level (0 V) :::

RF Characteristics

Operating Frequencies

The board supports the following LoRaWAN frequency channels shown in the table below. The frequency parameter is easy to configure as you go through the device configuration setup. RAK4200 has two different types based on its frequency: RAK4200(L) for low frequency and RAK4200(H) for high frequency.

Module	Region	Frequency (MHz)
RAK3172(L)	Europe	EU433
	China	CN470
RAK4200 (H)	Indian	IN865
	Europe	EU868
	North America	US915
	Australia	AU915
	Korea	KR920
	Asia	AS923

Electrical Characteristics

Electrical Consumption

Several current consumption ratings are provided below for a detailed RAK4200 WisDuo LPWAN Module usage. Refer to the values provided for specific simulations and calculations.

Operating Voltage

Feature	Minimum	Typical	Maximum	Unit
VCC	2.0	3.3	3.6	Volts (V)

Laboratory Testing

The following figures shown below are the average current consumptions based on the different test cases.

Materials:

• Power Consumption Meter
• RAK4200 WisDuo LPWAN Module

LoRa Packet Sending

The RAK4200 WisDuo LPWAN Module takes 53.155 ms to send a LoRa packet which consumes 68.4 mA of current.

• Sending Time: 53.155 ms
• Current consumption: 68.4 mA

Figure 7428: Oscilloscope Screen Capture of LoRa Packet Sending

LoRa Packet Receiving

The RAK4200 WisDuo LPWAN Module takes 46.179 ms to receive a LoRa packet which consumes 17.1 mA of current.

• Receiving Time: 46.179 ms
• Current consumption: 17.1 mA

Figure 7429: Oscilloscope Screen Capture of LoRa Packet Receiving

Operating Current

Feature	Condition	Minimum	Typical	Maximum	Unit
Operating Current	TX Power	68.4			mA
	RX Mode	17.1			mA

Sleep Current

Feature	Condition	Minimum (2.0V)	Typical (3.3V)	Maximum	Unit
Current Consumption	EU868	1.08	8.66		μA
	US915	1.14	9.40		μA
	CN470	1.13	7.88		μA

Schematic

Figure 7430: RAK4200 Module Schematic Diagram

Figure 7431: RAK4200 Module Reference Circuit

Mechanical Characteristics

Figure 7432: Mechanical Dimensions

Recommended Reflow Profile

• MSL Rating : Class 3

Figure 7433: Recommended Reflow Profile

Standard Conditions for Reflow Soldering:

• Pre-heating Ramp (A) (Initial temperature: 150 ℃): 1-2.5 ℃/sec;
• Soaking Time (T2) (150 ℃~180 ℃): 60sec-100sec;
• Peak Temperature(G): 230~250 ℃;
• Reflow Time (T3) (>220 ℃): 30~60 sec;
• Ramp-up Rate (B): 0~2.5 ℃/ sec;
• Ramp-down Rate (C): 1~3 ℃/ sec.

Software

Download the latest firmware of the RAK4200 WisDuo LPWAN Module as provided in the table below.

NOTE

The bin file contains the application code only, and you need the RAK DFU Tool to upload this file to the module.

The hex file contains both the bootloader and the application code. You need to use STM32CubeProgrammer to upload this.

Firmware

Model Source	Source
RAK4200	Download