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???
02/04/09 05:19
Modified:
  02/04/09 05:22

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#162019 - What about that logic card?
Responding to: ???'s previous message
Do you send the first (Motor1) logic card any inputs? Do you provide power? Do you provide an oscillator or other clock? How stabile is the output from the encoder? You say, " I have to Just Multipile the Pulse comming from encoder(Max 100KHz) and send it out.to other logic card which is going to control Motor 2, but what is LOgic card which I have no info. " Does that mean that the encoder always produces 100 KHz, exactly, or does it vary. If it varies, how much does it vary? Does it ever exceed 100 kHz? Does the duty cycle (time_high/time_low) ever change? Under what circumstances?

How precisely must you multiply the output from the encoder? How quickly must you respond to changes if there are any?

Do you know what a phase-locked-loop is? Have you ever looked at a CD4046 or 74HC7046? How about a frequency synthesizer, e.g. MC145157 <http://pdf1.alldatasheet.com/datasheet...57-2.html> and others of that series?

A phase locked loop is a circuit which uses a voltage controlled oscillator, a phase detector, and an error amplifier, possibly in combination with one or more dividers in order to produce a local copy of an input reference frequency, or a multiple of that frequency. A frequency synthesizer uses that same strategy to produce a desired frequency from another frequency of known value. In some cases very precise outputs can be derived from somewhat less precise inputs by complex and sophisitcated means. The cesium clock at the U.S. National Institute of Standards and Technology uses such techniques to provide very precise time references.

Please answer ALL the questions I've presented in this and previous messages regarding this problem of yours.

If you had already done so, you'd likely be finished now. Doing this sort of thing in the 100 kHz and lower range is quite achievable, but you must answer ALL the questions.

RE





List of 23 messages in thread
TopicAuthorDate
Frequency Multiplication            01/01/70 00:00      
   what is the wave form shape of the original signal?            01/01/70 00:00      
   Yes, PLL is the most promising solution            01/01/70 00:00      
   Easy integer approximation            01/01/70 00:00      
      Yes, but            01/01/70 00:00      
         Wave Shape            01/01/70 00:00      
            Constant speed?            01/01/70 00:00      
            Constant speed?            01/01/70 00:00      
            Constant speed?            01/01/70 00:00      
            Constant speed?            01/01/70 00:00      
            Still some outstanding questions            01/01/70 00:00      
            Perhaps you're looking at the wrong motor            01/01/70 00:00      
   Rate Multiplier            01/01/70 00:00      
      That might work ... but ...            01/01/70 00:00      
         Frequency multiplier            01/01/70 00:00      
            How about some numbers?            01/01/70 00:00      
               Frequency Multiplier            01/01/70 00:00      
                  I was afraid that was the case ...            01/01/70 00:00      
                     Frequency Multipllication            01/01/70 00:00      
                        What about that logic card?            01/01/70 00:00      
                           Frequency Multipiler            01/01/70 00:00      
                              Why no further relevant information?            01/01/70 00:00      
                                 I have been following this            01/01/70 00:00      

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