Recommend Projects


6 months ago 475
  • Description
  • Documents
  • BOM
  • Attachments
  • Members
  • Comments


This is a LoRa node, powered by the ESP32 WROVER-B microcontroller. ESP32-WROVER-B is a powerful, generic WiFi-BT-BLE MCU module that targets a wide variety of applications, ranging from low-power sensor networks to the most demanding tasks, such as voice encoding, music streaming and MP3 decoding. ESP32-WROVER-B features a 4 MB external SPI flash and an additional 8 MB SPI Pseudo static RAM (PSRAM). The LoRa module on this board is the RFM95W. The design has an onboard 868MHz antenna with 5dBi gain. More about this in the antenna section below. There is an external 32.768 kHz crystal connected between GPIO32 and GPIO33 to act as RTC sleep clock. The board is designed to be used for production ready solutions where code has been tested and verified rather than where you have to frequently upload new code. However if using Micropython. this will not be an issue.

Header And Pins A 24-pin header is provided for external connections. This also allows for modules to be designed specifically for this board and these can be plugged on to the 24-pin header. These modules can provide 5-V power to the board via pin 23 & 24 (both are 5V inputs) or take 3.3V power from the board via pins 1 & 3. GND is on pins 2 & 4. All pins connected to internal flash, RTC clock crystal or the on-board Lora Module are not exposed in the 24-pin header. Modules installed on the header are stackable as long as no two modules contend for any of the IO pins. However multiple modules can sit on the I2C bus. The Pinout of the 24-pin header is below.

24PIN Header.jpg

Programming This board does not contain a USB-UART interface. For programming or other USB connectivity, a seperate module with a USB-UART bridge controller should be used. Design documents (Schematic and PCB) are in this project [] (ESP32 LoRa Node Programmer). This can be connected to the 24-pin header to program the controller.

The board can be programmed using arduino IDE or micropython. I have tried without success to get pycom's version of Micropython to run on this but for some reason, firmware in flash gets corrupted once the board is power cycled. The latest version of [] (micropython with SPIRAM support here) works perfectly. However, if you wish to take advantage of the REPL without having the 24-pin header occupied by the USB-UART module, you can use [] (this Micropython) by Boris Lovosevic (Loboris). It provides Telnet and FTP access. This make sit possible to disconnect the USB-UART bridge module and connect to the board via telnet over WiFi. Files can be uploaded using ftp.

On-board Communication While the ESP32 module provides WiFi and Bluetooth Low Energy (BLE), there is an RFM95W LoRa module on the board. There is also an integrated antenna connected to this module through a matching LC network. The antenna is a 5dBi PCB antenna designed to Texas Instruments design note DN024 specification for 868MHz only. We have been able to achieve 5.99KM with this antenna in an urban area, where a stub antenna could only perform up to 1.5KM. Interrupt pins DIO0, DIO1 and DIO3 are all connected to GPIO23. The pin connections are as follows:

  • RADIO_MOSI------------GPIO27
  • RADIO_MISO------------GPIO19
  • RADIO_SCLK------------GPIO5
  • RADIO_NSS-------------GPIO18
  • RADIO_DIOO------------GPIO23
  • RADIO_DIO1------------GPIO23
  • RADIO_DIO2------------GPIO23

Power The board can be powered by external 5V input as described above. There is a socket for a 1S LiPo battery with onboard charging. Some battery connectors have their terminals swapped so the positive terminal is marked beside the connector. There is an onboard schottky diode to protect the board if terminals are swapped.


ESP32 Board

ESP32 Board PCB


ID Name Designator Footprint Quantity Manufacturer Part Manufacturer Supplier Supplier Part Price LCSC Assembly Mounted BOM_Supplier BOM_Manufacturer BOM_Manufacturer Part BOM_Supplier Part BOM_LCSC Assembly
1 2KΩ R4 0805 1 LCSC UniOhm 0805W8J0202T5E C1359
2 1uF C1 0805 1 LCSC FH 0805B105K500NT C29822
3 MBR120LSF D2,D3,D1,D4,D5 SOD-123FL 5 LCSC SK MBR120LSF C130880
4 MCP73831T-2ATI/OT U2 SOT-23-5 1 LCSC MICROCHIP MCP73831T-2ATI/OT C14879
5 XL-1206QPC(RED) CHRG,LED 1206 2 LCSC LCSC XL-1206QPC C10781
6 1.02KΩ R1,R6 0805 2 LCSC UniOhm 0805W8F1021T5E C17369
7 0Ω(0R0) R15,R16,R2,R3 0603 4 LCSC LIZ CR0603FA0000G C100699
8 0.1uF C3,C6,C12 0603-CAP 3
9 ESP32-WROVER U4 ESP32-WROVER 1 LCSC Espressif Systems ESP32-WROVER C129145
10 RFM95W U3 WIRELESS-LORA-RFM95WSMD 1 RS-Online RFM95W-868S2 125-1259
11 1.8nH L1 0603 1 LCSC FH VHF160808H1N8ST C1026
12 2.7pF C7 0603 1 LCSC SAMSUNG CL10C2R7CB8NNNC C16149 Yes
13 AMS1117-3.3_C347222 U1 SOT-223 1 LCSC Youtai Semiconductor Co., Ltd. AMS1117-3.3 C347222
14 32.768KHz X1 SMD-3215_2P 1 LCSC YXC YST310S32.768KHz12.5pF10ppm C94279
15 10KΩ R5,R7 0805 2 LCSC UniOhm 0805W8J0103T5E C25612
16 12pF C5,C9 0603 2 LCSC MuRata GCM1882C1H120FA01D C126539
17 22uF C2,C11,C8,C4 0805 4 LCSC Samsung Electro-Mechanics CL21X226MRQNNNE C307563
18 PH2.0-2PWB Horizontal 1SLIPO PH2.0-2PWB-HORIZONTAL 1 LCSC BOOMELE PH2.0-2PWB Horizontal C47647
19 300S-24P CN2 300S-24P 1 LCSC Shenzhen Cankemeng - C132440
20 K2-1107ST PROG,RST SMD-6.1X3.6 2 LCSC HRO K2-1107ST C118141




The owner does not allow comments in this project now

Comments (0)

如果需要转移工程请在个人中心 - 工程 - 工程高级设置 - 下载工程,下载后在 打开保存即可。
有问题联系QQ 3001956291 不再提醒
svg-battery svg-battery-wifi svg-books svg-more svg-paste svg-pencil svg-plant svg-ruler svg-share svg-user svg-logo-cn svg-double-arrow
We use cookies to offer you a better experience. Detailed information on the use of cookies on this website is provided in our Privacy Policy. By using this site, you consent to the use of our cookies.