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???
08/28/10 19:49
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 		 #178366 - 10% current variation already covered in text
Responding to: ???'s previous message
The article discussed a 12V battery and claimed a 10% variation in the reference LED driven by "constant current". So don't ridicule the claim when the full text did mention expected behaviour. And no 12V chargeable battery should be used until the voltage gets too low to drive that reference LED. For lead accid, the voltage should be within 10V and 15V.

But I don't understand his selection of R2 - if both resistors have the same value, then LEDvar will not be able to get 10mA for a full battery.

List of 40 messages in thread
TopicAuthorDate
Look Ma, I just invented the wheel!            01/01/70 00:00      
   not the first time            01/01/70 00:00      
      RE: also mentioned here            01/01/70 00:00      
   Hard to find previously unpublished ideas to write about            01/01/70 00:00      
      Stated Criteria for EDN "Design Ideas!            01/01/70 00:00      
         Low level of innovation involved            01/01/70 00:00      
   Look Ma, I just invented the wheel!            01/01/70 00:00      
      Student Project Idea            01/01/70 00:00      
   another goodie            01/01/70 00:00      
      LMGTFY            01/01/70 00:00      
         10% current variation already covered in text            01/01/70 00:00      
            how can you have            01/01/70 00:00      
               Different solutions for different needs            01/01/70 00:00      
                  just the fact it is not            01/01/70 00:00      
                     Still thinking "constant" is an absolute term            01/01/70 00:00      
                        I'm basing it on your statement            01/01/70 00:00      
                           The Actual Data            01/01/70 00:00      
                              Article still doesn't mention lead-acid batteries            01/01/70 00:00      
                                 Actually It Is Based on Lead Acid Battery            01/01/70 00:00      
                                    Might kill LED if testing while charging            01/01/70 00:00      
                                       Do Notice            01/01/70 00:00      
                                          Just modulation that is > 100 times larger            01/01/70 00:00      
                                             which no one has argued            01/01/70 00:00      
                                                But a 12V lead acid battery still doesn't hold 15V...            01/01/70 00:00      
                                                   two people            01/01/70 00:00      
                                                      Still living in a black or white world            01/01/70 00:00      
                                                         Black and White?            01/01/70 00:00      
                                                         I just hope ....            01/01/70 00:00      
                                                            Allegro?            01/01/70 00:00      
                                                               Allergo Variation            01/01/70 00:00      
   Reinventing the wheel isn't as bad as ...            01/01/70 00:00      
      New Model Introduced            01/01/70 00:00      
         Legal action            01/01/70 00:00      
         I must say ...            01/01/70 00:00      
            Hating them like the plague            01/01/70 00:00      
               classic wrong thinking            01/01/70 00:00      
               Business idea.            01/01/70 00:00      
                  appropriate optical filters            01/01/70 00:00      
            wheel re-invented            01/01/70 00:00      
               2012 Model on Drawing Board            01/01/70 00:00      

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