One of life's mysteries?

[davyboy]

Why don't LED bulbs light as soon as you turn turn the switch on?

[RootsBooster]

Why don't LED bulbs light as soon as you turn turn the switch on?

 

I've never experienced this

[petemcewan]

Davyboy,

 

The LED emitters themselves are certainly able to turn on instantly - on the order of nanoseconds. But your LED bulb is not just composed of an LED emitter, it has a buck converter that converts the AC voltage to a lower, DC-like voltage with limited current. It's not a transformer anymore, it's a switching regulator that "chops" the incoming voltage. That part of the circuit has apparently been badly designed and takes a moment to sense that it should turn on. There may even be a small microcontroller involved which in itself takes a moment to boot.

 

It's the quality of the "driver" that makes the difference. Good quality units should switch on without any perceptible delay.

[davyboy]

Davyboy,

 

 

It's the quality of the "driver" that makes the difference. Good quality units should switch on without any perceptible delay.

thank you.

[Janus]

Why don't LED bulbs light as soon as you turn turn the switch on?

 

Mine come on instantly. Are you referring to the ones that work off 240 volts or those that work via a transformer?

[Cyclone]

It would be due to having capacitors which take time to reach charge initially.