The Ebyte EoRa-S3-900TB wireless module development test board is a development test kit based on ESP32-S3FH4R2 chip and Ebyte LoRa module. The development board integrates a Type-C interface, E22-900MM22S LoRa module, 0.96-inch OLED display, SD card slot, lithium battery charging circuit and its power supply circuit.
| Subsystem | Parameter | Min | Typical | Max | Unit | Notes / Conditions |
|---|---|---|---|---|---|---|
| System & Power | Supply Voltage (VCC) | 3.2 | 3.3 | 5.0 | V | Guaranteed full RF output when > 3.3V; absolute max 5.5V |
| Operating Temperature | -40 | — | +85 | °C | Industrial-grade rating | |
| UART Logic Level | — | 3.3 | — | V | Non-5V tolerant; risk of burnout if 5V TTL applied directly | |
| Deep-Sleep Current | — | 21.74 | — | µA | Verified with Nordic PPK2 profiler | |
| WOR Active Current | — | 38.19 | — | µA | Average duty-cycle current using SX1262 CAD interrupt | |
| Continuous Polling Current | — | 45.00 | — | µA | Average current in active sensor node polling cycle | |
|
LoRa RF Engine (SX1262 / E22) |
Operating Frequency | 850 | 915 | 930 | MHz | Supports 868MHz / 915MHz regional ISM bands |
| RF Output Power | -9 | — | +22 | dBm | Software configurable | |
| Receiver Sensitivity | -147 | -146 | -145 | dBm | Measured at 0.3 kbps air rate (LoRa mode) | |
| Air Data Rate (LoRa) | 0.018 | — | 62.5 | kbps | Software configurable modulation | |
| Air Data Rate (FSK) | 0.6 | — | 300 | kbps | Software configurable modulation | |
| TX Peak Current | — | 120 | — | mA | Instantaneous power consumption at +22 dBm | |
| RX Active Current | — | 10 | — | mA | Continuous RF receive mode | |
|
Wi-Fi Subsystem (ESP32-S3) |
Frequency Band | 2412 | — | 2484 | MHz | IEEE 802.11 b/g/n (20/40MHz bandwidth) |
| Max Transmit Power | 18 | — | 21 | dBm | Per Espressif ESP32-S3 official datasheet | |
| Max Throughput | 1 | — | 150 | Mbps | Up to 11M (b), 54M (g), 150M (n) | |
| Receiver Sensitivity | -98.4 | — | -71.4 | dBm | Varies by data rate and modulation mode | |
| TX Current Consumption | 286 | — | 540 | mA | Peak power transmission load | |
| RX / Active Current | 88 | — | 91 | mA | Standard Wi-Fi active operation mode | |
|
Bluetooth LE (ESP32-S3) |
Frequency Band | 2402 | — | 2480 | MHz | Bluetooth 5.0 LE & BLE-Mesh support |
| Transmit Power | -24 | 0 | 20 | dBm | Multi-level adjustable RF power | |
| Data Rates | 0.125 | — | 2.0 | Mbps | Supports 125K, 500K, 1M, and 2M Phys | |
| Receiver Sensitivity | -104.5 | — | -93.5 | dBm | Higher sensitivity achieved at lower PHY bitrates | |
| TX Current Consumption | — | — | 580 | mA | Peak BLE transmission current | |
| RX / Active Current | — | — | 95 | mA | Standard BLE active operation mode |
Ultra-Low-Power & Battery Life Validation
Unlike typical LoRa boards with ambiguous sleep ratings, the EoRa-S3-900TB's low-power architecture is rigorously verified in real-world deployments:
- Verified Deep-Sleep Currents: Achieves 21.74 µA in basic deep sleep, ~38.19 µA average current in active LoRa WOR duty-cycle monitoring, and ~45 µA in continuous sensor network polling (profiled using Nordic PPK2).
- Wake-On-Radio (WOR) & CAD: Utilizes SX1262 Channel Activity Detection (CAD) interrupts to keep the MCU sleeping 99.9% of the time, waking strictly when RF packets or events occur.
- Multi-Year Battery Lifespan: Designed for event-driven telemetry, a standard 3000 mAh LiPo battery can easily power the node for 8+ years.
Developer pitfalls/hardware design tips
In the factory hardware routing, DIO1 is tied to GPIO33. Please note that GPIO33 is not an RTC-capable pin for external wake. For ultra-low-power applications requiring hardware DIO1 interrupts to wake the ESP32-S3 from deep sleep, developers can reroute DIO1 to <strong>RTC_NUM_16 (GPIO16).
| Main parameters | performances | note | |
| minimum value | maximum values | ||
| Supply Voltage | 0 V | 5. 5 V | Supply voltage above 5.5 V may cause module burnout |
| LoRa Blocking Power | - | 10 dBm | Less likely to burn out in close proximity |
| operating temperature | -40 0 C | +85 ° C | industrial grade |
| Product parameters | Parameter value | describe |
|---|---|---|
| Limit parameters | voltage | 0‑5.5V, exceeding 5.5V may cause the module to burn out |
| LoRa blocking power | 10dBm, less likely to be burned when used at close range | |
| Operating temperature | ‑40℃~+85℃, Industrial grade standard | |
| Machine parameters | Whole machine working voltage | 3.2‑5V, >3.3V can guarantee the output power |
| UART communication level | 3.3V, there is a risk of burning if using 5V TTL | |
| Wi‑Fi parameters | Working frequency | 2412‑2484MHz |
| Maximum transmit power | 18‑21dBm, please refer to Espressif ESP32‑S3 manual for details | |
| sending rate | 1‑150Mbps
|
|
| Receive sensitivity | ‑98.4~‑71.4dBm | |
| Emission current | 286‑540mA | |
| Working current | 88‑91mA, see Espressif ESP32‑S3 manual for details | |
| BLE parameters | Working frequency | 2402‑2480MHz |
| Transmitting power | ‑24‑20dBm | |
| Transmitting rate | 0.125‑2Mbps | |
| Transmitting current | 580mA | |
| Working current | 95mA | |
| Receive sensitivity | ‑104.5~‑93.5dBm | |
|
LoRa parameters
|
Working frequency | EoRa‑S3‑400TB: 410‑493MHz
|
| Transmit power | ‑9‑22dBm | |
| Transmitting current | 120mA, instantaneous transmission power consumption | |
| Transmitting current | 10mA, usually receiving current | |
| air rate | FSK mode, software configuration: 0.6‑300Kbps
|
|
| Ideal Comm Range | Ideal communication range 6000M, test conditions: clear and open environment, antenna gain 5dBi, antenna height 2.5 meters, LoRa air rate 0.34kbps, actual measurement in open areas. | |
| internal LoRa module parameter | Crystal frequency | 32MHz, passive crystal oscillator |
| Modulation | GFSK/LoRa, LoRa is recommended | |
| Packaging method | SMD type | |
| Interfaces | SPI | |
| Dimensions | 10×10×2.5 mm | |
| Antenna Interface | SMA/U.FL, characteristic impedance approx. 50 ohms |
| NO | Main hardware | Component Introduction |
|---|---|---|
| 1 | E22‑400MM22S or E22‑900MM22S | E22‑400MM22S and E22‑900MM22S are ultra‑small size independently developed by Chengdu Ebyte Electronics Co., Ltd. based on the new generation of LoRa radio frequency chips SX1268 and SX1262 produced by American Semtech and are suitable for 433MHz, 470MHz‑868MHz and 915MHz patch‑type LoRa wireless modules. |
| 2 | ESP32‑S3 chip | ESP32‑S3 is a low‑power MCU system‑on‑chip (SoC) that supports 2.4GHz Wi‑Fi and bluetooth LE wireless communications. |
| 3 | 3D omnidirectional antenna (Wi‑Fi antenna) | Maximum gain 4.9dBi, 2.4G Wi‑Fi omnidirectional antenna |
| 4 | IPEX seat (Wi‑Fi antenna) | IPEX first generation socket, 2.4G Wi‑Fi antenna |
| 5 | IPEX seat (LoRa antenna) | IPEX first generation seat, LoRa antenna |
| 6 | SMA radio frequency interface (LoRa antenna) | Full length 14.5mm SMA head, LoRa antenna |
| 7 | Reset key | reset button |
| 8 | switch | For completely disconnecting battery power |
| 9 | GPIO external interface | GPIO from ESP32‑S3 |
| 10 | GPIO external interface | GPIO from ESP32‑S3 |
| 11 | External battery interface | SH1.25mm, 2pin battery interface |
| 12 | Single color LED | Addressable RGB LED, driven by GPIO8 |
| 13 | Bicolor LED | Charging indicator light, red when charging, green when fully charged |
| 14 | OLED screen | 0.96‑inch OLED screen |
| 15 | Boot key | Download button. Press and hold the Boot key and press the Reset key to enter the "firmware download" mode and download the firmware through the serial port. |
| 16 | USB download port | USB interface: can be used as the power supply for the development board or the communication interface between PC and ESP32‑S3 chip |
| 17 | TF card slot | Short body TF card slot |
| 18 | Pin | All available GPIO pins (except the SPI bus of the flash) have been led to the pin headers of the development board. Please see pin headers for more information. |
| NO | Pin Name | Pin type | Pin Usage |
|---|---|---|---|
| 1 | VCC | power supply | Power pin, can be used as 5V power output after normal power supply |
| 2 | GND | power supply | Power GND |
| 3 | VDD | power supply | The power pin can be used as a 3.3V power output after normal power supply. At this time, it is forbidden to input another external power. |
| 4 | GND | power supply | Power GND |
| 5 | GPIO42 | Input Output | — |
| 6 | GPIO46 | Input Output | — |
| 7 | GPIO45 | Input Output | — |
| 8 | GPIO41 | Input Output | — |
| 9 | GPIO40 | Input Output | — |
| 10 | GPIO39 | Input Output | — |
| 11 | U0RXD | Input | UART serial port RXD |
| 12 | U0TXD | Output | UART serial port TXD |
| 13 | GPIO38 | Input Output | — |
| 14 | GPIO16 | Input Output | — |
| 15 | GPIO15 | Input Output | — |
| 16 | RST | Input Output | Connect to ESP32‑S3 reset pin |
| 17 | GPIO08 | Input Output | Connect to the reset pin of the LoRa module |
| 18 | GPIO12 | Input Output | — |
| 19 | GPIO48 | Input Output | — |
| 20 | GPIO47 | Input Output | — |
| 21 | GPIO33 | Input Output | Connect to DIO1 of LoRa module |
| 22 | GPIO34 | Input Output | BUSY connected to LoRa module |
| 23 | GPIO35 | Input Output | — |
| 24 | GPIO0 | Input Output | BOOT button connected to the base panel |
| 25 | GPIO36 | Input Output | — |
| 26 | GPIO57 | Input Output | LED connected to base plate |
Community-Proven Open Source Projects
1. Ultra-Low-Power HVAC System Monitor
A real-world community project by developer William Lucid on Hackster.io demonstrates the full potential of the EoRa-S3-900TB ("EoRa Pi") in ultra-low-power, event-driven IoT architectures.
- Application Overview: A three-node HVAC heating system monitor utilizing LoRa Wake-On-Radio (WOR), ESP-NOW, deep sleep, and direct Google Sheets logging.
- Measured Low-Power Performance: Verified with a Nordic PPK2 Power Profiler, the outdoor sensing node achieves an outstanding average deep-sleep current of ~38.19 µA (spending 99.9% of its time in deep sleep). Theoretical battery life exceeds 8 years on a standard 3000 mAh LiPo battery.
- Hardware Flexibility: Demonstrates seamless coordination between the onboard ESP32-S3 and SX1262 LoRa module. By utilizing Channel Activity Detection (CAD) interrupts and RTC wake capabilities, periodic wakeups are completely eliminated—waking the node only when environmental or system status changes occur.
Full Project & Source Code: 1、Read the full article on Hackster.io | 2、View GitHub Repository
2. Ultra-Low-Power Long-Range Environmental Sensing Network
Development engineer William Lucid (AB9NQ-William) completed the LoRa Standalone Sensor Network project based on the EoRa-S3-900TB module (powered by the Espressif ESP32-S3 and Semtech SX1262 chips), and completely open-sourced it on the tech platform element14 Community and GitHub. This practical project successfully verified 915MHz LoRa long-range wireless telemetry integrated with I2C and GPIO/RTC interrupt interfaces, supported BME280 multi-sensor (temperature, humidity, atmospheric pressure) environmental monitoring, 74HC04 signal redirection, and radio/deep sleep modes, and achieved up to 7km long-range wireless data transmission with ultra-low baseline current (~20–22µA in deep sleep, ~45µA active node cycle) and cloud-ready Docker/Flask dashboard integration. View the original test process and technical documentation.
Note: The examples on this page are from the open-source technology community and only demonstrate the actual application effects of the products in development scenarios. Copyright belongs to the original authors and does not represent the original authors' commercial endorsement of our company or products. If there are any copyright issues, please contact us for removal. We offer a free product sponsorship program for developers to help them advance their projects.
FAQ Section
1. Does the onboard OLED display consume significant power during transmission testing?
The 0.96-inch OLED is highly energy-efficient and serves as a vital diagnostic tool for field testing. For ultra-low-power sleep mode testing, the display can be programmatically disabled using the ESP32-S3 GPIO pins, ensuring that your battery life measurements remain accurate to your actual deployment requirements.
2. Can I use this development board to evaluate LoRaWAN protocol stacks?
Yes. Because the board integrates the high-performance ESP32-S3 and the E22 LoRa module, it is fully compatible with standard LoRaWAN firmware libraries (such as LMIC or LoRaMac-node). It provides the necessary hardware abstraction layer to test both point-to-point and LoRaWAN network architectures.
3. Is the lithium battery charging circuit compatible with all standard 3.7V cells?
The onboard charging circuit is designed for standard 3.7V lithium-ion/lithium-polymer batteries. We recommend ensuring that your battery pack includes a protection board to prevent over-discharge. The Type-C interface provides a standard 5V input, making it easy to charge the unit via standard power banks or PC ports during outdoor development work.
