I plan to put an Arduino onboard of my hub-generator powered bicycle circuitry.
Currently, I have a circuit consisting of:
- 6V/3W AC hub generator (variable frequency and power);
- Rectifier bridge;
- 6v/5W Zener regulator;
- 6800 uF electrolytic capacitor;
With this circuit, I can safely drive anything needing 6V up to the 3W limit.
Now for the Arduino, I'd want to provide 5V at
Vin, and for that I would like something like this:
GNDwith a 5V Zener (and possibly a generous capacitor);
- insert some voltage drop between 6V output and
- drive external loads with transistors (BC 548 have served me well for up to 100mA per transistor);
- (of course) ground everything together;
But I am not sure if voltage-dropping is a good practice, or if I would find a suitable diode with the desired drop.
If everything I proposed is b*shit, I would like some guidance, preferably involving only simple components. Absolute efficiency is not a must, and I can leave with some lost current through the regulators (zeners for example).
Update: I plan to add a battery to this circuit, but it should be able to run only from generator by design, anyway.
More update: I have read something about "Low Drop Out" regulators (LDO). Can I build one myself? Is there any off-the-shelf, widely available component for that? Can I use some of these together with the Zener and the capacitor, or it wouldn't make sense then?
Yet another update: a coworker suggested the TPS-76650 (Texas). Are there "non-proprietary" components with similar characteristics?