Monday, January 14, 2019

regulated switched LED regulator designs (experimental)

the thing ::


how to set it up in practice . . . involves a number of tests ::

  1. Detach the mosfet and the feedback Mod line -- from simulation and from build
    Regulate the frequency and duty to match those of the simulation
  2. Re-attach the mosfet , ( /!\ /!\ /!\ ) set some 20Ω or greater in series with the 6LF22 to limit the current through LED-s --and-- set electrical fuse or limitting resistor in series with the LED-s --or-- double the number of LED-s ( /!\ /!\ /!\ ) - - - - - - - - - we are going to verify the transformer ::
    do the same mods on the simulation and test for the differences . . .
    -- if the real build performs worse you need to recalculate and rebuild the transformer accounting for resistance not present in ↑this↑ circuit
    -- if the build performs better then the primary side is "over-driven" the timing of the switching wave-forms has to be re-evaluated and adjusted
  3. Attach the Mod line --and-- ( /!\ /!\ /!\ ) set the regulation to be greater than in simulation (!! dont remove electrical fuse or extra LED-s !!) ( /!\ /!\ /!\ ) ,
    -- regulate it bit below the desired LED current (in case the regulation failure -- the regulator has to be re-designed --or-- replaced with better known one)
  4. if everything worked out so far the additional tests are required such as ::
    • test for bit higher than simulated input voltage (the Cl batteries may have up to 1.8V per cell e.g. 10.8V for fresh 6LF22)
    • test for battery contact strobe !!!
      -- here everything can fail -- use fuses and perhaps build a protective controller that can fast switch off the circuit under test
    • test for the lower than in simulation input voltage !!!
      -- may result in oscillations failure and the MOS-FET being "constantly ON" (attempting to remain in conduction mode) . . .
    • etc. ...

Basic simple ::


add VCO , Mod2 divider , the 2 to 4 decoder and a current sense / +integrator -- and it's basically done . ..


[Eop]

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