Identifying & Replacing A Fake FTDI FT232R Chip | Voltlog #314

Lately I’ve been getting a few of these serial interfaces from aliexpress, this is just a RS232 to TTL level converter while this one is a USB to RS485 interface and it’s great that we can buy these for cheap for we are getting exactly that, something cheap. This converter chip is likely not of the best quality and not to mention this FT232 chip is certainly not a genuine one. 

There is nothing worse than having to deal with communication issues and debugging your tools instead of the actual project you are working on so I’ve decided to replace these chips with some genuine, good parts because the pcb and the rest of the circuit should be fine as long as we have a good conversion chip in there.

You might be wondering if there is any way to tell for sure that you’ve got an FTDI FT232R clone. There are at least 2 methods that I know you can use. First one is to install an older version of the driver which FTDI released in 2014, after plugging your fake FTDI depending on the driver version it will either disable the FT232 chip by writing something to it’s internal EEPROM or it will modify it so that it shows a custom alert message over serial instead of your actual data. I don’t like this method, because there is a better, simpler way, you can simply check for the serial number of the FT232 which you can get from the device manager under windows or by using the FT_Prog utility. If your serial number is A50285BI or 00000000 then you most certainly have a fake chip because that is a popular serial number which is written to fake chips. They don’t bother changing the serial number on the fakes, they mostly write the same number or set it to zero.

One thought on “Identifying & Replacing A Fake FTDI FT232R Chip | Voltlog #314”

  1. I have lot of them but recently I bought 4 on ebay and I got all A50285BI serial number, even worst, I can’t change or configure it because there is no eeprom inside. Also there is difference in the handling of CTS/RTS handshake that make it incompatible with my projects.
    The other fake one have no issue.

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