3 ms·
Great article. What are the design decisions that affect the amount of flicker? Is it solely based on electronically smoothing out the input voltage, or are t
by nkurz 7y ago
Great article. What are the design decisions that affect the amount of flicker? Is it solely based on electronically smoothing out the input voltage, or are there other factors? For example, are there phosphors that are better at smoothing the white light even if the blue is modulated?
- yeutterg 7y agoAdding capacitance to a "linear" driver design is one way to reduce modulation, with some tradeoffs. There are other power supply designs, such as switch-mode and several variations of "constant current" drivers, which could reduce modulation at a higher cost. Adjusting the frequency also plays a role in mitigating perceived flicker. In higher-end drivers, you'll often see a hybrid approach, such as constant current between 5 and 100% and PWM below 5%. Drivers with deep dimming down to 0.1% are just using 10-bit PWM. This would be difficult to do in a bulb form factor. I haven't seen any meaningful research into the persistence of various phosphors. It's an interesting thought. My guess is that there could be some effect, but usually we would just try to improve the power electronics.
- jacobush 7y agoI heard IKEA uses the phosphor
- yeutterg 7y agoTheir non-dimmable filament bulbs (silver base) tend to be pretty low flicker, but I found the dimmable ones (gold base) have upwards of 30% flicker, even at full output. Without having done a teardown, I suspect the flicker is due to the power electronics.