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???
06/13/08 20:06
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 		 #155883 - DEAD wrong
Responding to: ???'s previous message
I omitted the capacitor that goes from supply to ground, it's for decoupling purposes
DEAD wrong ANY chip that does not have a 10-100nF cap mounted DIRECTLY at it (I refuse layouts where vthe trace is more than 5mm) is likely to fail. EACH AND EVERY chip on your board should be properly decoupled. (if this is 'flying leads' you are in trouble anyhow).

Your power supply decoupling is in series with a significant inductance (the wire/trace) and is totally non-functional at the switching speeds of modern chips. Also an electrolytic is dysfunctional at anything abobe ~100kHz

Erik

List of 45 messages in thread
TopicAuthorDate
I'm getting insane! pls help!            01/01/70 00:00      
   I do not know much about Arghmel, but            01/01/70 00:00      
      >Arghmel<, Erik, are you crazy?            01/01/70 00:00      
         fair warning to all            01/01/70 00:00      
   Thanks for the props but....            01/01/70 00:00      
      have you tried changing the chip            01/01/70 00:00      
   Yep            01/01/70 00:00      
      the Arghmel users should wake up soon            01/01/70 00:00      
         The Problem Often Is The ...            01/01/70 00:00      
            I'll try that            01/01/70 00:00      
               But....            01/01/70 00:00      
                  What breed of MAX232?            01/01/70 00:00      
                     so...            01/01/70 00:00      
                        Trainer Board            01/01/70 00:00      
                           um quite similar...            01/01/70 00:00      
                        Your schema looks fine            01/01/70 00:00      
                           a strange thing has happened            01/01/70 00:00      
                              470uF            01/01/70 00:00      
                                 Just wanted to state the same            01/01/70 00:00      
                              It would have to be a very good 470uF cap ...            01/01/70 00:00      
                                 Richard??            01/01/70 00:00      
                                    What negative effect would that be?            01/01/70 00:00      
                                       let's do that, you start            01/01/70 00:00      
                        DEAD wrong            01/01/70 00:00      
   Oh uh......            01/01/70 00:00      
      Wrong Xtal may be            01/01/70 00:00      
         0.1uF ok then            01/01/70 00:00      
            Are you sure?            01/01/70 00:00      
               I found a usable one            01/01/70 00:00      
                  Did you find the reason            01/01/70 00:00      
                     still searching for the reason            01/01/70 00:00      
            Model of a capacitor            01/01/70 00:00      
         18.432MHz for Std Baud Rates ...            01/01/70 00:00      
   Shorts,shorts,shorts,            01/01/70 00:00      
      Pictures?            01/01/70 00:00      
         why is that?            01/01/70 00:00      
            Just Curious            01/01/70 00:00      
               Hey uh Jon i had already removed all socketed ICs            01/01/70 00:00      
      Vss for logical chips SHOULD be ground            01/01/70 00:00      
         Stupid me, i meant Vcc not Vss            01/01/70 00:00      
         Let\'s call this a day            01/01/70 00:00      
            Good Luck!            01/01/70 00:00      
               Thank you all            01/01/70 00:00      
   Boot loader running?            01/01/70 00:00      
      I'll try it tonight            01/01/70 00:00      

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