The Ebyte E103-W20 (7688) is a highly integrated, low-power SMD Wi-Fi routing module powered by the MediaTek MT7688AN/MT7628AN SoC running at a 580MHz MIPS24KEc core, supporting the OpenWrt OS and IEEE 802.11b/g/n protocols with up to 24dBm RF transmit power for reliable 200m serial-to-Wi-Fi transparent data transmission and rich interface secondary development.
| Parameter Item | MT7688NN / MT7688AN Specification | MT7628NN / MT7628AN Specification |
|---|---|---|
| Core Processor | MediaTek MIPS24KEc (580MHz CPU Main Frequency) | |
| Operating System | OpenWrt Linux / Custom Embedded Development Supported | |
| Wi-Fi Protocol & Band | IEEE 802.11b/g/n (2.4 GHz) | |
| Antenna Architecture | IPEX x 1 (1T1R / 1T2R, up to 150Mbps PHY rate) | IPEX x 2 (2T2R MIMO, up to 300Mbps PHY rate) |
| Transmission Power | 20 to 24 dBm | |
| Communication Distance | 200 meters (Ideal line-of-sight conditions) | |
| Flash / DDR2 Memory | 32MB SPI Flash (16MB/8MB customizable) / 128MB DDR2 RAM | |
| Hardware Interfaces | 5x 10M/100M Ethernet (1WAN, 4LAN), 3x UART, SDIO, SPI, I2C, I2S, PWM, GPIOs | |
| Supply Voltage / Current | 3.3V DC (Absolute Max: 3.5V) / Peak Supply Capability >= 1000mA | |
| Product Size / Weight | 34.1 x 18.7 x 2.7 mm / 3.5g | 36.1 x 18.7 x 2.7 mm / 3.5g |
| Electrical parameters | unit | model |
Remark | ||
| E103-W20（7688） | E103-W20（7688） | ||||
| working voltage | V | 3.3±0.2V | Voltage over 3.5 V will permanently burn the module | ||
| communication level | V | 3.3 | Voltage over 3.5 V will permanently burn the module | ||
| No-load running current | mA | 180±50 | Average power consumption | ||
| Supply Current Requirement | mA | ≥1000 | |||
| temperature | Operating temperature |
℃ | -20～+55 | Industrial grade | |
| Storage temperature |
-40～+85 | ||||
| humidity | use | %RH | 10～95(non-condensing) | ||
| storage | 5～95(non-condensing) | ||||
| Hardware parameters | model | Remark | ||
| E103-W20（7688） | E103-W20（7688） | |||
| chip |
MT7688NN | MT7628NN | ||
| Flash | 32MB | Customizable 16MB/8MB | ||
| Memory |
DDR2 128MB | Customizable DDR2 256M/64M/32MB | ||
| Memory |
MIPS24KEc | |||
| Packaging method patch | SMD | |||
| Antenna interface | IPEX×1 （1T2R 2.4 GHz with 150Mbps PHY data rate） |
IPEX×2 （2T2R 2.4 GHz with 300Mbps PHY data rate） |
Characteristic impedance about 50 ohms | |
| interface | Ethernet interface |
5 10M/100M adaptive | Interfaces supported by factory default firmware 1WAN, 4 LAN . | |
| UART | 3 way |
The interfaces supported by the firmware are 2-way UART with transparent transmission function . |
||
| SDIO | 1 way | Firmware interface not supported | ||
| SPI | 1 way | Firmware interface not supported | ||
| I2C | 1 way | Firmware interface not supported | ||
| I2S | 1 way | Firmware interface not supported | ||
| PWM | 1 way | Firmware interface not supported | ||
| GPIO | 8 or more Firmware | Supported Interfaces Defined Functions | ||
| size | 34.1*18.7*2.7mm | 36.1*18.7*2.7mm | The error size is ±0.1mm | |
Practical Application Scenarios
1. Smart Industrial IoT Gateways and Edge Routers
In industrial automation, field engineers deploy the E103-W20 (7688) module within compact edge computing devices to bridge legacy fieldbus hardware with cloud infrastructure. Utilizing its 5x 10M/100M adaptive Ethernet ports configured as 1WAN and 4LAN alongside the Linux OpenWrt distribution, the module establishes a stable wireless routing network. Field data collected from PLCs via the module's transparent transmission UART ports is processed locally or instantly pushed to central servers over an IEEE 802.11b/g/n Wi-Fi pipeline.
2. Multi-Channel Commercial Smart Vending Machines and Interactive Kiosks
Modern outdoor vending networks demand processing capabilities alongside high-speed data pipelines to handle inventory tracking, multimedia ads, and cashless payment security. B端 hardware designers integrate the MT7628AN-based module featuring 2T2R MIMO architecture with up to 300Mbps PHY data rate over dual IPEX external antennas. This deployment guarantees reliable network operation in dense urban settings, allowing continuous communication for transactional APIs while utilizing the built-in MIPS 580MHz CPU for custom peripheral control.
3. Distributed Environmental Telemetry and Industrial Wireless IP Cameras
For wide-area remote surveillance or environmental logging inside processing plants, engineers combine the E103-W20 module with low-profile high-gain external antennas via the on-board IPEX receptacles. The module operates securely up to 200 meters using an optimized 24dBm RF transmit power. By leveraging its native SDIO, SPI, and I2C hardware multiplexing lines, the OpenWrt core interfaces directly with high-resolution image sensors, audio inputs, and toxic gas sensor clusters, transforming the module into a compact, low-cost smart wireless telemetry end-node.
FAQ Section
1. What are the strict power supply design constraints required to prevent module instability or failure under full load?
The E103-W20 (7688) module operates at a nominal voltage of 3.3V DC. However, during burst Wi-Fi packet transmissions at full 24dBm output power, the transient current consumption spikes significantly. System engineers must design an external LDO or buck converter loop capable of supplying a continuous current of at least 1000mA. Furthermore, the input voltage must never exceed the absolute maximum electrical rating of 3.5V, as over-voltage exposure will permanently degrade the MT7688AN/MT7628AN silicon die.
2. How does the default firmware architecture support UART serial-to-Wi-Fi transparent data transmission?
The factory-flashed default firmware utilizes two optimized UART ports to implement plug-and-play transparent serial data streaming. When raw serial characters are piped into the module's RX pins, the network stack automatically wraps the payload into TCP/UDP packets and routes them over the active Wi-Fi link without requiring complex AT command handshakes. For more comprehensive customizations, developers can flash custom Linux images using the OpenWrt SDK to leverage the remaining hardware pins.
3. What is the technical difference between the MT7688NN and MT7628NN variants of this wireless routing module series?
The core distinction lies in the antenna architecture and maximum throughput capabilities. The MT7688NN variation utilizes a 1T1R/1T2R physical antenna layer via a single IPEX connector, supporting a maximum physical layer data speed of 150Mbps. Conversely, the MT7628NN variant features a dual IPEX layout utilizing 2T2R MIMO architecture, which doubles the maximum wireless PHY data rate to 300Mbps, providing superior multi-path signal reception and data throughput for network-heavy applications.
4. Which hardware peripherals can be mapped out for custom secondary development using the OpenWrt operating system?
By utilizing the open-source OpenWrt Linux ecosystem, embedded developers gain direct access to the rich peripheral register set of the MediaTek MIPS core. Although the default firmware focuses primarily on Ethernet and UART routing, secondary code can unmask and control 1x SDIO channel for storage expansion, 1x master SPI bus for interfacing external memory, 1x I2C bus for digital sensor readouts, 1x I2S interface for high-fidelity audio pipelines, and up to 8 independent GPIO channels mapped to custom PWM logic.
