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

Back to Subject List

Old thread has been locked -- no new posts accepted in this thread
???
12/23/06 13:48
Read: times


 		 #130047 - is there any other way?
Responding to: ???'s previous message
Thanks. Well, putting C or RC across error amp works but as I said in first post it causes a decrease in sensitivity of error amp and it causes problem at higher frequencies. The sine wave that is given to error amp is produced digitally by DDS(Direct Digital Synthesis) and its upper limit is 100KHz. So I'm looking for other ways (other than alternative feedback path) to stabilize loop. I could not find much information in text books and application notes but after extensive search in internet I found some articles that suggested I should limit bandwidth of power amp. There was no more information of how someone should do that.
The only thing that came to my mind was that they mean I should use an LPF but as I said it definitely exacerbate the problem due to phase shift of filter. So I'm wondering is there any way other than alternative feedback path to stabilize the loop.


List of 30 messages in thread
TopicAuthorDate
How should I limit bandwith of amplifier?            01/01/70 00:00      
   That's how an OPamp works            01/01/70 00:00      
      you mean I have to choose a correct power amp?            01/01/70 00:00      
         Pure C ?            01/01/70 00:00      
            is there any other way?            01/01/70 00:00      
               putting C or RC across error            01/01/70 00:00      
                  More opamps can exacerbate the problem            01/01/70 00:00      
         The idea was..            01/01/70 00:00      
            you are very corect but...            01/01/70 00:00      
               ???            01/01/70 00:00      
                  sorry, I had not read your first post carefully            01/01/70 00:00      
                     the laboratory that has ordered            01/01/70 00:00      
                        ???            01/01/70 00:00      
                           This is the first ....            01/01/70 00:00      
                     OP 07            01/01/70 00:00      
                        right            01/01/70 00:00      
                        slewrate is very low            01/01/70 00:00      
                           Thats the problem            01/01/70 00:00      
                              waveform shape is not the immediate concern            01/01/70 00:00      
                     How?            01/01/70 00:00      
                        Re: How            01/01/70 00:00      
                           Why not measuring voltage drop across load?            01/01/70 00:00      
                              @100KHz?            01/01/70 00:00      
                                 Yes !            01/01/70 00:00      
                                 Yes, of course!            01/01/70 00:00      
                                    Re:Yes            01/01/70 00:00      
                                       Much much easier!            01/01/70 00:00      
   Even more problems...            01/01/70 00:00      
      Spec.            01/01/70 00:00      
      Phase, capacitive load            01/01/70 00:00      

Back to Subject List