Email: Password: Remember Me | Create Account (Free)

Back to Subject List

Old thread has been locked -- no new posts accepted in this thread
???
06/16/12 05:59
Read: times


 		 #187724 - Solved
Responding to: ???'s previous message
Solved the noise issues. The main change I made was

1. Insert Ferrite bead + 100 ohm between board ground and remote RS232 ground.
2. Insert Ferrite bead + 330 ohms in Rx line of RS232 (incoming RS232 line).
3. Insert FB + 330R in Tx of local MAX232. (Not really required..)

Chip is very sensitive to noise from serial port side. It simply hangs. Our 100 MBPS ethernet board (designed using wiznet 5300 + F340 at 48 MIPs) works very well under the same noisy conditions). Inserting 100 ohms + FB between MAX 232 AND F232RL also seemed to help.


- Raj Nambiar

List of 36 messages in thread
TopicAuthorDate
FTDI F232RL Noise issues            01/01/70 00:00      
   GND,cables            01/01/70 00:00      
      of this is it, then            01/01/70 00:00      
   leakage effects..            01/01/70 00:00      
      Thanks for the comments..            01/01/70 00:00      
         changing the serial port data....            01/01/70 00:00      
         cable, bought off the shelf            01/01/70 00:00      
            Test standard solutions            01/01/70 00:00      
               Options..            01/01/70 00:00      
                  VCP /D2X            01/01/70 00:00      
                     Problem exists with both drivers            01/01/70 00:00      
                  Aten serial to USB cable uses a FTDI chip            01/01/70 00:00      
   FTDI chip ESD sensitivity            01/01/70 00:00      
      Thanks Oliver...            01/01/70 00:00      
         Zeners are slow            01/01/70 00:00      
         show Your circuit            01/01/70 00:00      
            F232 is USB powered but.. + circuit            01/01/70 00:00      
         USB Isolator Chips            01/01/70 00:00      
            Isolators            01/01/70 00:00      
         Better than zeners            01/01/70 00:00      
            just a thought            01/01/70 00:00      
               Layout            01/01/70 00:00      
                  VCP/Direct drivers            01/01/70 00:00      
                  Layout attached            01/01/70 00:00      
                     It's a high speed circuit !!!!            01/01/70 00:00      
                        Totally 100% Agreed            01/01/70 00:00      
                           the trouble with schematics ....            01/01/70 00:00      
                              Bandwidth limitation            01/01/70 00:00      
   22 ohms between serial port ground and FT232 ground helps...            01/01/70 00:00      
      of course it does            01/01/70 00:00      
         Erik,            01/01/70 00:00      
            Links please            01/01/70 00:00      
               Link...            01/01/70 00:00      
                  Solved            01/01/70 00:00      
                     Magnetics            01/01/70 00:00      
                        Ethernet input is connected to serial port ground            01/01/70 00:00      

Back to Subject List