FT245RL weird behavior. Fakes?

• FT245RL weird behavior. Fakes?
  Posted by meneerbeer on 02 Nov, 2015 13:59
• Hi, first post here, not sure if this is the correct subforum for this.
  
  I recently bought some FT245RLs from China (I know bad idea) for some custom designed PCBs. The FT245RL is a USB to parallel FIFO.  After receiving everything, I soldered some FT245RLs to my PCBs and of course, the circuit was not working. 
  
  Ok, so I started debugging. I read out the FT245RL with FT PROG and it recognizes as a 'FT232R'. I asked someone with a similar (working) circuit) to read out his. His identifies as a 'FT245R'.
  
  The FT232R is a USB to serial converter. Therefore my next step was to figure out if my "FT245R" showed the same behavior as you would expect from a FT232R. I probed pin 1 with a logic analyzer, which is the TXD pin of an FT232R. I sent some data to the FT245RL and guess what I see on my logic analyzer, serial output:
  
  
  So at this point I can only conclude that the FT245RLs I received are disguised FT232RLs. I am in discussion with the supplier and I get the following respone: "Our FT245RL chips which is correct ones as we shipped,we have other clients who bought this item from us before,never have problem."
  
  The supplier seems to be asking me to cut off all pins of the ICs I received before I get my money back.. I want to be absolutely sure I am not doing something wrong before I do that. Am I missing something? Can the FT232RL for instance be easily reprogrammed to a FT245RL, which is why I am having problems with them? Why would you package FT232RLs as FT245RLs? That does not make any sense at all? 
• #1 Reply
  Posted by bktemp on 02 Nov, 2015 14:22
• I had exactly the same problem some years ago. But my FT245RL were bought from Digikey, so it is unlikely they were fakes.
  My guess is, FTDI screwed up the labeling of the parts. Maybe FT232 and FT245 use the same silicon and the output interface is beeing configured at some step during production?
  Since all parts from one delivery behaved the same I got new parts.
  
  I have used the wrong FT245RL as FT232RL and they work fine, so they are fully functional FT232RL.
  Maybe the faulty labeled parts from Digikey/FTDI ended up in China and are now beeing sold there.
• #2 Reply
  Posted by meneerbeer on 02 Nov, 2015 14:34
• I sent FTDI an email to ask if they can confirm the misslabeling. Not sure if they would ever admit it..