* These are Tibbo BASIC/C-programmable devices and their function depends on the loaded app.
We offer many ready-to-use apps, among them a serial-over-IP (SoI) app and Modbus Gateway app.

RJ203 Jack/Magnetics Front-End

The RJ203 is an RJ45 jack/magnetics front-end add-on module designed to work with the Davicom DM9000B Ethernet controller.

The RJ203's patented design allows you to put other components right under it, and thus minimize the required host PCB size. The bottom portion of the device's front face is translucent. Place status LEDs directly on the host PCB under the RJ203, and they will be visible through the front face of the module.

You can also use the RJ203 in combination with the EM1206 and EM203 modules, which fit right under the RJ203.



  • Incorporates a standard RJ45 jack.

  • 10/100BaseT magnetics onboard:

    • RJ203: compatible with the DM9000B controller IC;
    • RJ203A: compatible with the DM9000EP controller IC.
  • Mates with the EM203 and EM1206 modules.

  • Dimensions (LxWxH): 31 x 20 x 15.5mm.

  • Patented design minimizes required host board space.

See Also:

  • EM1206 programmable IoT module
  • EM203 serial-to-Ethernet module


RJ203 Hardware Manual

Order the RJ203 and related parts

Not available in the U.S.
RJ203+EM1206 module combination.
Not available in the U.S.
RJ203+EM203 module combination.
Not available in the U.S.