Digital Mist Coolant Pump

[stupoty]

LED's don't strobe if they are run off pure d.c. as in a battery or off a well filtered power supply. Many commercial supplies don't bother to filter well and LED's have short enough response time to act as a strobe. Additionally many LED drivers that have dimming capability use pulse width modulation technology which does turn the LED off and on at the modulation frequency.

What many people don't realize is that white LED's are actually fluorescent devices. The phosphors are being excited by the blue LED underneath instead of a mercury vapor discharge. All phosphors have a persistence which means that the phosphor continues to glow for a short time after the energization source has been removed. I have not done any measurements as to the actual persistance but it is apparently somewhere on the order of 10 msec.

Bob

Thanks for the correction, I will try and retain that

Not sure if I repeated something told to me or just having a brain fart. In my head though I'm sure I can remember seeing this with red led's but as you say with a linear DC supply I could detect no strobeing with high power white LED's. (or red)

Stuart