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???
08/28/10 17:16
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 		 #178359 - another goodie
Responding to: ???'s previous message
In the latest print (thus no link) issue of EDN there is a design idea "Simple battery-status indicator uses two LEDs"

This circuit has a LEDref in series with a 10k resistor in series across the battery terminals and the article states
a) "which operates at a constant current of 1mA"
b) "the intensity of LEDref remains constant for a battery state from a fully charged state to a fully discharged state.
I really wonder how a 10k in series with a LED can provide constant current, let alone how a fully discharged battery can illuminate a LED.

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   Hard to find previously unpublished ideas to write about            01/01/70 00:00      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