Connii MM

Connii MM is discontinued as of May 2007. It has been replaced by Connii MM 2.0

Connii MM – I2C Fast Mode Interface for USB, I2C Multimaster and Monitor

Connii MM is a small, compact, easy-to-use solution for a PC driven I2C transmitter and receiver. The I2C interface works as an I2C multimaster device. Thus, it is able to drive buses running multiple I2C bus masters.

Additionally, Connii MM is a limited I2C monitor for traffic up to 400kHz.

This multimaster behaviour and the I2C monitor are the main differences between Connii MM and Connii, which is a singlemaster only.

The unit is connected to a PC via a standard USB port. Both I2C modes standard (100 kbit/s) and fast (400 kbit/s) can be selected as speed of operation. The device has two connectors – a standard USB plugin and a PS/2 connector for your I2C bus.

In case you are looking for a more sophisticated I2C USB interface please check Tracii XL 2.0, the sole I2C interface supporting the I2C high speed mode.


The product comes with the most advanced I2C software package on the market, it is featured by the telos I2C Framework and runs under the sophisticated I2C Studio. Labview VIs are included running different I2C modes.

All the software is for free, there are no hidden fees!


  • PC connection via USB bus
  • I2C connection via Mini-DIN connector
  • I2C buses operating at a range of 2.7 – 5.5 Volt can be attached


  • 100 kbit/s (Standard Mode) and 400 kbit/s (Fast Mode), the actual rate slighly depends on the I2C bus termination.
  • I2C master receiver/transmitter transfers including repeated start
  • 7 and 10 bit addressing
  • I2C via Internet
  • Extensive software package including interfaces for C++, C#.NET, Java, Labview, Delphi 8Python and NXP’s (formerly Philips Semiconductors) URT/URD.
  • Superior Windows application I2C Studio
  • Usage of several telos I2C interfaces including Tracii XL / Tracii XL 2.0 at the same computer via different USB ports, thus you can drive multiple I2C buses from a single PC!
  • Future-proof product: Firmware completely downloaded via USB
  • Compact size: The 68*41.5*27.5 mm sized plastic housing protects the device from damages.
  • USB powered, no external power supply necessary.
  • TCP/IP Network support (I2C via Internet)
  • ESD protected I2C, IEC compatibility according to
    EN 61000-4-2 (ESD): Air – 15kV, Contact – 8kV


  • The I2C Monitor does only recognize regular I2C transfers, no I2C error conditions etc., thus it is not well suited for finding problems on I2C communication level. The monitor stretches SCL, in particular on SCL clock speeds above 120kHz, i.e. the SCL line is held low occasionally. That may lead to problems with master or slave devices that do not support SCL stretching (like some I2C single master implementations).
    Tracii XL 2.0 offers a more sophisticated I2C Monitor, which includes time stamps for every byte and error recognition.
  • For proper tracer mode operation, please connect additional pullup resistors of 7 kOhm or less to SDA and SCL.


  • The actual device (68*41.5*27.5 mm plastic housing)
  • Software package I2C Framework including all listed components
  • Application I2C Studio

Related Products

You may of course use standard cables already available at your lab. The PS/2 cable quality might have impacts on the signal quality on the I2C bus.


This product comes with a bunch of software licensed for the lifetime of the product. Additionally you get a free service contract. This includes 12 months free support plus all software updates coming within this period. You may use all this software without time limitations.