I have this falstad-circuit: enter image description here

And here it is per request, as a SCH file screen:

enter image description here

I'm trying to use a 555 astable to convert a variable AC with maximum of 12V (coming from Bicycle Hub) to 8VDC, enabling me to store it in batteries. Additionally there will be an overcharge circuit that redirects the current to the LEDs in case the batteries are empty.

Here are a couple of questions:

  • I wanted to know if what I have done here is correct.
  • I would like to point out that when I replicate this in tinkercad the simulation fails.
  • And when importing the BRD to Eagle, the connections seem to be recalculated and what I get, might not produce the appropriate result.
  • Why is the current produced no longer stable when I connect the LEDs?
  • Is there any other option to achieve AC to DC for battery storage, with the AC coming from a HUB?
  • Would this circuit work in reality?

Thank you!

Simulated in LTspice, falstad and tinkercad and by altering the zener the circuit drops the output voltage successfully.

Here is a LTspice screen (yeah the naming is different.. yada yada):

enter image description here

Also by increasing the C2 to 40uF the voltage comes even more stable and the leds don't flicker.

After a suggestion to use a regulator, i have done just that.

enter image description here enter image description here

Now I will be looking into the charging circuit.

  • 1
    \$\begingroup\$ Your circuit looks like a fairground in the late evening. A regular circuit diagram without all the falstad nonsence would make reading it easier without being distracted by all the crappy falstad "features". \$\endgroup\$ – Andy aka Jul 23 at 7:33
  • \$\begingroup\$ Just added a Eagle SCH screencap. \$\endgroup\$ – VΛVΛV Jul 23 at 10:07
  • 1
    \$\begingroup\$ It would be useful if you would label your components. For example there are 9 diodes of varying types, none of them labeled. Please make them D1 - D9 and so on for the other components. I have two observations. What is the significance of the 9.94V in the top RH corner? It appears to be the input AC half wave rectified . The output from the bridge rectifier is across a 10uF capacitor in parallel with a zener diode, there is nothing to limit the current through the diode. Have you thought of using a simple 3 terminal regulator after the bridge rectifier and capacitor? \$\endgroup\$ – Peter Jennings Jul 23 at 10:07
  • \$\begingroup\$ Welcome to EE.SE! Regarding C1 and UZ1, ground points downwards. In general, power supply components go vertical for this reason and signal flow is horizontal. It won't help your circuit here, just a friendly reminder to keep it readable. \$\endgroup\$ – winny Jul 23 at 10:32
  • \$\begingroup\$ A suggestion: Stick to one design program. As you've noticed, conversions can cause problems. Learn one, stick with it. I usually recommend KiCAD because it is capable, it is free, and it is under active development. It won't hit you up with artificial limits like the "free" versions of commercial software or lock you into a painful microcosm like Fritzing. \$\endgroup\$ – JRE Jul 23 at 10:53

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