Skip to main content

RAK2245 Pi HAT WisLink LPWAN Concentrator Datasheet

Overview

Description

The RAK2245 Pi HAT WisLink LPWAN Concentrator is a module with Raspberry PI form factor. It can be plugged into Raspberry PI such as Raspberry Pi 3 Model B+ as a complete RF front end of gateway. It supports eight channels and is available for LoRaWAN global frequency bands. The board is the smallest gateway concentrator which integrates the Ublox MAX-7Q GPS Module and heat sink.

The board can provide low data rate LoRa radio links at ultra-fast speed. It is powered by a Semtech SX1301 transceiver concentrator that is capable of managing packets from many remotely dispersed end-points. Two Semtech SX125X are integrated for RF front end I/Q transceivers.

The RAK2245 Pi HAT is a complete and cost efficient gateway solution that can help you develop a full LoRa system. This is an economical way to create different solutions like smart grids, intelligent farms and other IoT applications. It is also ideal for manufacturing small series that can expand into more applications.

Features

  • Compatible with Raspberry Pi 3 Model B+ edition
  • Integrated Ublox MAX-7Q GPS Module and heat sink
  • SX1301 base band processor, emulates 49 x LoRa demodulators, 10 parallel demodulation paths, supports 8 uplink / 1 downlink channels
  • Two (2) units of SX125x Tx/Rx front-ends for high/ low frequency
  • Supports 5 V power supply, integrated level conversion circuit
  • TX power up to 27 dBm, RX sensitivity down to -139 dBm @ SF12, BW 125 kHz
  • Supports latest LoRaWAN 1.0.2 protocol
  • Supports global license-free frequency band (EU433, CN470, EU868, US915, AS923, AU915, KR920 and IN865)
  • Supports SPI, UART, I2C interface

Specifications

Overview

The overview shows the top view of the RAK2245 Pi HAT board and its corresponding outer dimension. It also presents the block diagram that shows how the board works.

Board Overview

RAK2245 Pi HAT Module with Raspberry Pi connector is shown above, it has outer dimensions of 56 x 65 x 22 mm (±2 mm).

Figure 9943: RAK2245 Pi HAT WisLink LPWAN Concentrator Dimensions

Block Diagram

Figure 9944: RAK2245 Pi Hat Block Diagram

Hardware

The hardware is categorized into five parts. It discusses the interfacing, pinouts and its corresponding functions and diagrams. It also covers the parameters and standard values of the board in terms of electrical and environmental.

Interface

The SX1301 digital baseband chip contains ten (10) programmable reception paths. Those paths have differentiated levels of programmability and allow different use cases. It is important to understand the differences between those demodulation paths to make the best possible use of the system.

Power Supply

RAK2245 Pi HAT module is powered through 5 V or 3.3 V power pins.

SPI Interface

The pin connector provides an SPI connection which allows direct access to the SX1301 SPI interface. This gives the target system the possibility to use existing SPI interfaces to communicate with the module.

NOTE

Reset SX1301 via Pin 11 after turning on RAK2245 Pi HAT.

UART and I²C

UART and I2C connections are also included on the pin connector. These connections allow direct access to the GPS module. The 1PPS is connected internally to SX1301.

Digital IOs

There are two (2) digital IO PINs, which give the user an interface to reset the GPS module or set it into standby mode.

LEDs

There are three (3) Green LED that indicate the status of PWR, TX, RX.

Antenna RF Interface

The modules have two RF interfaces for LoRa and GPS antennas over the standard UFL connectors (Hirose U. FL-R-SMT). It has a characteristic impedance of 50 Ω and supports both Tx and Rx via RF ports, providing the antenna interface.

Pin Definition

The pin connector of RAK2245 Pi HAT is located at the bottom side. Refer to the diagram and table below for the description and numbering of each pins.

Figure 9945: Pinout Diagram
PinNameDescription
13.3V3.3 V Supply Voltage
25V5 V Supply Voltage
3SDAI²C SDA (Connect to GPS Module I²C_SDA)
45V5 V Supply Voltage
5SCLI²C SCL (Connect to GPS Module I²C_SCL)
6GNDGround
7NCNo Connection
8UART_RXDIt should be connected to RASPBERRY PI’s UART_TXD. This pin is connected to GPS Module’s UART_RXD internally.
9GNDGround
10UART_TXDIt should be connected to RASPBERRY PI’s UART_RXD. This pin is connected to GPS Module’s UART_TXD internally
11RESETSX1301 RESET (GPIO17 of Raspberry Pi)
12NCNo Connection
13NCNo Connection
14GNDGround
15NCNo Connection
16NCNo Connection
173.3V3.3 V Supply Voltage
18NCNo Connection
19SPI_MOSIIt should be connected to RASPBERRY PI’s SPI_MOSI. This pin is connected to SX1301’s SPI_MOSI internally.
20GNDGround
21SPI_MISOIt should be connected to RASPBERRY PI’s SPI_MISO. This pin is connected to SX1301’s SPI_MISO internally.
22NCNo Connection
23SPI_CLKIt should be connected to RASPBERRY PI’s SPI_SCLK. This pin is connected to SX1301’s SPI_CLK internally.
24SPI_CSIt should be connected to RASPBERRY PI’s SPI_CE0. This pin is connected to SX1301’s SPI_CS internally.
25GNDGround
26NCNo Connection
27ID_SDI²C_SDA for HAT ID EEPROM
28ID_SCI²C_SCL for HAT ID EEPROM
29NCNo Connection
30GNDGround
31NCNo Connection
32NCNo Connection
33RESET_GPSGPS Module Reset Pin (GPIO 13 of Raspberry Pi)
34GNDGround
35STANDBY_GPSGPS Module standby PIN (GPIO19 of Raspberry Pi)
36NCNo Connection
37NCNo Connection
38NCNo Connection
39GNDGround
40NCNo Connection

RF Characteristics

Operating Frequencies

The board supports all LoRaWAN frequency channels as below. Which is easy to configure while building the firmware from the source code.

RegionFrequency (MHz)
EuropeEU433, EU868
ChinaCN470
North AmericaUS915
AsiaAS923
AustraliaAU915
KoreaKR920
IndianIN865
Transmitter RF

The RAK2245 Pi HAT has an excellent transmitter performance. It is highly recommended to use an optimized configuration for the power level configuration, which is part of the HAL. This results in a mean RF output power level and current consumption.

PA ControlDAC ControlMIX ControlDIG GainNormal RF Power Level (dbm)
0380-6
03100-3
031400
13934
13808
139010
1311012
1312014
1313016
2312017
2313019
2314020
331000
331100
3312025
3313026
3314027
  • At T=25° C, Vdd = 5 V (Typical) if nothing else stated
ParameterConditionMinTyp.Max
Frequency Range863 MHz870 MHz
Modulation TechniquesFSK/LoRa
TX Frequency Variation vs TemperaturePower Level Setting: 20-3 kHz+3 kHz
TX Power Variation vs TemperaturePower Level Setting: 20-5 dBm+5 dbm
TX Power Variation-1.5 dBm+1.5 dBm
Receiver RF

We recommended that you to use optimized RSSI calibration values which are part of HAL v3.1. For both Radio 1 and 2, the RSSI-offset should be set to -169. The following table gives the typical sensitivity level of RAK2245 Pi HAT.

Signal Bandwidth (kHz)Spreading FactorSensitivity (dBm)
12512-139
1257-126
25012-136
2507-123
50012-134
5007-120

Electrical Characteristics

The following are the electrical characteristics of RAK2245 Pi HAT. Contact the RAK support if you need other details for your project.

Absolute Maximum Rating

The values and range given below are all in accordance with the Absolute Maximum Rating System (IEC 134).

ParameterDescriptionMin.Typ.Max
Supply Voltage (VDD)Input DC Voltage-0.3 V5.0 V5.5 V
Operating TemperatureTemperature Range-40° C-+85° C
RF Input Power---15 dBm
NOTE

With RF output power level above +15 dBm a minimum distance to a transmitter should be 1 m for avoiding too large input level.

Maximum ESD

The table below lists the maximum ESD.

ParameterMinTypicalMaxRemarks
ESD sensitivity for all pins except ANT11 kVHuman Body Model according to JESD22-A114
ESD sensitivity for ANT11 kVHuman Body Model according to JESD22-A114
ESD immunity for ANT14 kVContact Discharge according to IEC 61000-4-2
8 kVAir Discharge according to IEC 61000-4-2
NOTE

The module is an Electrostatic Sensitive Device and requires special precautions when handling.

Power Consumption
ModeConditionMinTypicalMax
Active-Mode (TX)TX Enabled and RX Disabled336 mA
Active-Mode (RX)TX Disabled and RX Enabled360 mA

Environmental Requirements

Operating Conditions

The table below lists the operation temperature range.

ParameterMin.TypicalMaxRemarks
Normal Operating Temperature-40° C+25° C+85° CFully functional and meets 3GPP specifications

Firmware

Download the latest firmware of RAK2245 Pi HAT in the table provided below.

ModelRaspberry Pi BoardFirmware VersionSource
RAK2245 Pi HatRaspberry Pi 3B+ and 4V4.2.5RDownload

Models / Bundles

Ordering Information

Part NumberPackageDescription
RAK2243-0X-R011x board, 1x LoRa Antenna and 1x GPS Active Antenna retail packageSupports 433 / 470 / 868 / 915 / 923 / 920 / 865 MHz
RAK2243-0X-C1010-piece board and Antennas carton packageSupports 433 / 470 / 868 / 915 / 923 / 920 / 865 MHz

Certification