SME291 | Print |

Serial - UDP Ethernet Module with filtered RJ45 Connector



General Information

SonMicro Serial UDP Ethernet converter modules come with two hardware options both have the same firmware. One is called SME290-Mini and the other is SME291. SME291 is a compact module integrated with 5V regulator circuit and the LF1S022 RJ45 Ethernet connector. SME291 module may be used apart from the device or PCB. It requires only power supply pins and UART TX/RX pins to the main device or circuit. This is the more practical option if compared with SME290-Mini module. SME291 can be used inside the product enclosure or can be connected externally.

SME290/291 is a true Serial-to-Ethernet converter that connects a serial device to the LAN/WAN or internet, based on UDP protocol. Unlike TCP/IP , UDP protocol is a connection-less protocol, is similar to UART / RS232 and can be a better choice for embedded and industrial applications in most cases.

SME290/291 does not require any external microcontroller or PC to be controlled; it simply translates Ethernet and Serial data to each other with the minimum latency based on UDP protocol.

SME290/291 Ethernet module can be used with existing serial devices without any design change in hardware. Virtual Com Port is not supported, so software side should use UDP Sockets. UDP Socket examples comes with evaluation kits. Using UDP Sockets is easier than using a com port.  Alternatively, by using two of SME29X ethernet devices at both end of communicating devices, any two of these serial devices can be connected as "Virtual Wire", resulting in; no software change and so no need to use UDP sockets in the existing systems. Available RS232 software can be used in this manner.

SME290/291 is very simple to use after getting know few main parameters of the Ethernet network.

SME290/291 is a very effective design that does not require any design obstacles, and a serial device can be connected to the world just in minutes.

For rapid prototyping, demonstration or application development we recommend you to buy a low cost evaluation kit from our online store.




  • Connects any serial device to LAN/WAN/Internet
  • True Serial-Ethernet Conversion. No Control Mechanism is required.
  • Plug & Play, no need for initializations in run-time.
  • Can be created a "Virtual Wire", if two of ethernet module connected both ends of communicating devices. There wont be any need of any software implemantation or change with "Virtual Wire" implemantation.
    Existing serial devices can connect each other just in seconds, and apart from each other even in world's different places.
  • Based on UDP protocol, 10BaseT
  • Wide input voltage range. On Board 5V regulator (SME291)
  • Serial/UART Interface up to 115200bps (57600bps Default)
  • Configurable thru UART/RS232 or Ethernet (LAN)
  • Firmware Upgrade-able with encrypted ROM images
  • Ideal for embedded applications, better alternative than RS485.
  • Ideal for existing serial devices.


Pricing Information


Reference price for 100 pcs $27.9/ea
Better prices are available for higher quantites.

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Please Click to go Serial Ethernet Support page for:

  • Datasheet
  • User Manual
  • Application Notes
  • Upgrades
  • Software Downloads
  • Knowledge Base
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