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Author Topic: USB to I2C Master Reference Designs?  (Read 16318 times)


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USB to I2C Master Reference Designs?
« on: May 04, 2023, 01:22:57 AM »

Hi all! Does nayone know of any reference schematics that can support USB to I2C as a master? I am trying to provide an I2C interface used for communicating to an SFP+ transceiver (would as as the slave device) in my project. I am considering using the FTDI FT232HL chip to handle the interface conversion, but I couldn't find a good reference schematic pertaining to I2C applications. Any help is appreciated!

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Re: USB to I2C Master Reference Designs?
« Reply #1 on: May 04, 2023, 04:48:13 PM »


There are a few products which you can consider as a USB to I2C master.

The I2C master devices that we have are as follows.
All will require some form of application code running on the OS to control the device:

Using MPSSE and d2xx:
See AN_135 MPSSE Basics. Also MPSSE software examples exist.
UM232H is available for test, evaluation and reference.

Using LibFT4222 and d2xx:
Software examples are provided with the library download.
UMFT4222EV-D is available for test, evaluation and reference.

HID class device
LibFT260 can be used with Windows, software examples are provided with the LibFT260 library download.
UMFT260EV1A is available for test, evaluation and reference.

Schematics are provided in the modules linked above.

Note that the FT602 is not an appropriate product. This is a UVC video class device with built-in I2C master interface for video device configuration, not for general I2C master usage. It's likely the FT602 is overkill if you are just looking for an USB to I2C master bridge.

Best Regards,
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