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???
08/28/10 23:15
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 		 #178377 - just the fact it is not
Responding to: ???'s previous message
The quality of "constant current" is just a question of needs. In some applications, 0.01% variation is too much. When driving a single LED, 10% is very good

I have no beef with "When driving a single LED, 10% is very good" just the fact that naming a simple resistor drive from a voltage that varies ~40% "constant current" is ridiculous. A current that varies 40% (or even the erroneously claimed 10%) is NOT a constant current.

I have no "battery knowledge" to validate the design as such, so my comments have no relation to that, but an apple is not an orange just like 40% variation is not constant. Likewise, when I have tried to start my old truck and finally given up, when all I get is a click, is the battery voltage still 10V?

Erik

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   Hard to find previously unpublished ideas to write about            01/01/70 00:00      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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