Multiplexing in displays of LED pixels is necessary to minimise the number of drivers needed but it is also used to "increase" the perceived brightness of some vehicle lights.
I don't doubt that this is true.Multiplexing in displays of LED pixels is necessary to minimise the number of drivers needed but it is also used to "increase" the perceived brightness of some vehicle lights.
then it would be theoretically possible to totally eliminate the pulsatile nature of that light output (of the array of LEDs as a whole)
Yes, I understand all that.The pulsatile nature of that light output can be minimised when using a multiplexed array of LED elements to create a single source of light that appears to be brighter than the sum of the brightnesses of the individual elements when driven by maximum constant current. .... Information displays using a multiplexed array of LED elements to display text or graphics can be made to appear up to 5 times brighter than an element would be it run at maximum constant current but the mark space ratio of the light from an individual element ( pixel ) would be as low as 1 ( ON ) to 10 ( OFF ) or even lower.
That's obvious. They're for sawing tables with.what exactly are you hoping to do with the table saw ??
As you will be aware, all LED emitters need some form of current control. This is likely to be a simple buck or boost (depending on battery and emitter voltages) switch mode converter - even a really simple relaxation regulator. Such a converter can be made a lot simpler (ie cheaper) if you just don't bother about smoothing - so how much effort (ie cost) do you think goes into.most of them !... but it would surprise me if simple battery-operated LED lights used pulsed current, ...
As I keep asking, even in cheap, battery-operated, lights??As you will be aware, all LED emitters need some form of current control. This is likely to be a simple buck or boost (depending on battery and emitter voltages) switch mode converter - even a really simple relaxation regulator.
Yes, I'm aware of them (and, in fact, have some), but that doesn't really answer any of the questions I asked.There are LED elements that have a semi-conductor resistor diffused into the element. These elements can be connected directly to a voltage source, typically 3 volts from a pair of 1.5 volt batteries enabling long strings of low power LEDs lights to be easily manufactured.
Well yes, the answer is always going to be "it depends". But I'd be "not at all surprised" if something like a portable workshop light actually had a CC driver in it.As I keep asking, even in cheap, battery-operated, lights??
Maybe things have changed, but what I've often seen in cheap battery-operated lights is the LED elements strung together in series string(s), such that the total Vf was quite close to the battery voltage, and then with just a single resistor limiting the current (but dissipating very little) - and a resistor is always going to be cheaper than even the cheapest and nastiest of SMPSUs!
I agree, but the cheaper the product, the more surprised I'd be.Well yes, the answer is always going to be "it depends". But I'd be "not at all surprised" if something like a portable workshop light actually had a CC driver in it.
True. In fact, most of the LED bulbs/'lamps' (BC, ES etc. - NOT 'work lamps' ) have taken apart (particularly the cheaper ones) have had just a bridge rectifier and a capacitor.Actually, mains powered LEDs have less need for an SMPSU since the voltage is high (allowing many LEDs in series if needed and still headroom for a current control impedance) and the voltage relatively stable.
Create a stroboscopic effect with a cordless lamp and cut my arms off
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