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michka:research:microbial_fuel_cells:cardiff6 [2017-09-17 14:35] – michkamichka:research:microbial_fuel_cells:cardiff6 [2017-09-17 14:37] (current) – michka
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    * About one hour after the start of the experiment, it was charged at 0.25 V.    * About one hour after the start of the experiment, it was charged at 0.25 V.
    * After letting it overnight, it was only charged at 1.9 V, and we could not see any charging activity with a typical multimeter.    * After letting it overnight, it was only charged at 1.9 V, and we could not see any charging activity with a typical multimeter.
-   * We would have expected a charge reaching 2.5 V, which is the maximum rating of the supercap…+   * We would have expected a charge reaching 2.5 V, which is the maximum rating of the supercap...
  
 //Consequences on the PHS design// //Consequences on the PHS design//
   
-   * … it is actually a limitation of the S882-Z chip, which will only charge up to 1.8 V (according to the datasheet).+   * ...it is actually a limitation of the S882-Z chip, which will only charge up to 1.8 V (according to the datasheet).
    * This means that our supercap will only charge up to 1.8 V, which is not sufficient to power the BBC microbit    * or even open the 1381 voltage detector, which opening rising voltage limit is at 2.4 V.    * This means that our supercap will only charge up to 1.8 V, which is not sufficient to power the BBC microbit    * or even open the 1381 voltage detector, which opening rising voltage limit is at 2.4 V.
    * This means that we need another boost converter or charge pump using the 1.8 V charged supercap energy to bring it up to 2.4 V to activate the 1381 voltage detector, and then power the BBC microbit enough to open the gate of the 2N3904 feeding itself longer directly from the energy source.    * This means that we need another boost converter or charge pump using the 1.8 V charged supercap energy to bring it up to 2.4 V to activate the 1381 voltage detector, and then power the BBC microbit enough to open the gate of the 2N3904 feeding itself longer directly from the energy source.
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      * Could the second boost converter/charge pump replace the need for a post-Beam circuit (1381 voltage detector + transistors), by directly powering the BBC microbit in the appropriate conditions ?      * Could the second boost converter/charge pump replace the need for a post-Beam circuit (1381 voltage detector + transistors), by directly powering the BBC microbit in the appropriate conditions ?
      * Could we put some MFC in series, and use a different charge pump with a higher supply/input voltage, but a higher output voltage to directly power the BBC microbit from the charge pump ?      * Could we put some MFC in series, and use a different charge pump with a higher supply/input voltage, but a higher output voltage to directly power the BBC microbit from the charge pump ?
-     * Circuit design constraints+     * Circuit design constraints :
        * Few and available (not outdated) components, big enough to be soldered with Fablab equipment.        * Few and available (not outdated) components, big enough to be soldered with Fablab equipment.
        * Available (and not outdated) components.        * Available (and not outdated) components.
  • michka/research/microbial_fuel_cells/cardiff6.txt
  • Last modified: 2017-09-17 14:37
  • by michka