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User avatar
By sparkfun-sr
#208126
Hello.
Using FTDI chips for RS485 converter (USB to RS485)
For making RS485 converter we can use FT232RL chip, FT230X chip and FT231X chip from FTDI company.
The FT232RL chip has been around for years, but the two FT230X and FT231X chips are new.
Since the dimensions and prices of the two FT230X and FT231X chips are lower than the FT232RL chip, we therefore want to use the FT230X or FT231X chip.

The question is, are the two FT230X and FT231X chips recently produced and marketed without problems? Has anyone used these two chips? And was that okay? Don't these two chips have a fault for working permanently?
Thanks
User avatar
By TS-Chris
#208127
I cant speak to the FT230X, but we've used the FT232RL and FT231X on our designs for years and have never had any issues with them.

Just make sure you're getting genuine FTDI parts and not knockoffs and you should be just fine.
User avatar
By sparkfun-sr
#208170
Hi
Thanks for your reply
We used the FT232RL and ADM485 chips for the USB to RS485, but after 4 hours of continuous work, the FT232RL went wrong and we had to reconnect the converter from the USB port.
Could this be a problem with our design? In our design the RESET base and CTS, RTS, DCD, DSR, DTR basese of FT232RL chip are free and no connection!
Do we have to connect the CTS stand to the RTS stand and the DSR stand to the DTR stand and the DCD stand in the design? Is it better to connect these pins to each other to prevent FT chip error?

Another question is whether the ADM2587 chip can be connected to the FT230X/FT231X chip! We supply voltage to the ADM2587 and FT230X/FT231Xchips by powering 5V USB! Can the logical surface of the ADM2587 chip be easily connected to the FT230X/FT231Xchip?
User avatar
By TS-Chris
#208178
We used the FT232RL and ADM485 chips for the USB to RS485, but after 4 hours of continuous work, the FT232RL went wrong and we had to reconnect the converter from the USB port. Could this be a problem with our design?
I'm afraid I can't assist with your design, you'd need to consult a electrical engineering firm for design help. You might consider contacting FTDI to see how they recommend using the FT232RL and if any changes to your connections might be needed.

Assuming you don't have a design issue, it could have been a hiccup on your computer that caused the FTDI to lose communication with the computer. You'd need to do more testing to see if that was a one time event or something that keeps happening. You might even try a different computer to see if the issue is only on that one computer.


Another question is whether the ADM2587 chip can be connected to the FT230X/FT231X chip!
I don't immediately see a reason why not. You may need to review the data sheets for both parts to be certain no logic level conversion is needed, and if it is, add the appropriate circuitry. Again, we're not able to assist with that but if anyone else viewing this thread has advice, please post.