re: Old man rant - the new “low watt” light bulbs suck

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That's how they make "noise" in circuits and simply being hooked up to 60 Hz AC that is already turning them on and off 60 times/second is detrimental to their durability.

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I am not 100% sure I understand what you are saying. LEDs are not significantly impacted by strobing them. LEDs are used in many functions where they strobe constantly. One example many people have in their homes is a LED backlit TV. There is no negative effect on LEDs with turning them off and on like incandescent bulbs. That is why they work so well in some many applications.

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That's why they need extra circuitry to fix their flickering and not cause headaches.

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The need extra circuitry to function and not just to reduce flicker. The need DC current. They will first need a bucking transformer, then a 4-diode bridge rectifier, then a capacitor for the filter circuit, and a regulation circuit to produce stable voltage you still have a bit of a saw tooth wave (all positive polarity) after the filter portion of the driver circuit. This is all you need for some LED applications but in others, you will need a pulse width modulation circuit to strobe the LED for variable light output. This is a VERY simple circuit and I imagine most LED drivers in bulbs use a constant current source circuit with a couple of transistors, a couple of resistors, a diode (maybe), and a PWM controller (if they are dimmable).

Some people are more prone to flicker induced headaches than others. The problem is low frequency non-visible. The old tar ballast fluorescent bulbs flickered at 120hz which is apparently right in the sweet spot to cause certain people headaches. LED drivers almost always have flicker designed into them but a well-designed one will use much higher frequency flicker. If it is dimmable it should be designed so the lowest frequency output is higher than what is known to trigger headaches. Again the high frequency on-off cycling does not effect longevity in LEDs.



As I was typing this it struck me it would be interesting to wire a house with a single bucking transformer at the load center and run all the lighting circuits from it. It would be more energy efficient, reduce the part count/cost in the individual bulbs, reduce the heat in the bulbs by taking out the primary heat producer which should increase longevity, and potentially reduce the cost of wiring by using smaller gauge wire but might not always be the case since lighting circuits would have to be independent of all the 120v circuits for everything else. The problem with this is it would complicate wiring in the walls/ceiling since the low and high-voltage wires have to be separated to meet NEC and you would have to have separate boxes for switches where you had ceiling fan and light switches again due to the required separation of hi and low voltage.