Flashing LEDs

[Cemoi]

Has anybody tried flashing LEDs like this one?
Sounds interesting for a "be seen" bike light, as it does not seem to need a timer to generate the flashes. But only 15 cd, much less than a Nichia.
I wonder how it works, an IC integrated in the LED?

 

[greenLED]

The current concensus as far as bike LED blinkers go is that the Planet Bike SuperFlash is *the* light to get.

The new "Cherry Bomb" from PT sounds interesting, but I've yet to seen first-hand reviews about it.

 

[znomit]

Thats a good find. I went looking for some red ones a while back for a DIY build and could only find 12V.
Yes they have a built in circuit for the flashing.

 

[moimies]

Well, for flashing a led you don't need timer anyway: flip-flop.

 

[Steve K]

Has anybody tried flashing LEDs like this one?
Sounds interesting for a "be seen" bike light, as it does not seem to need a timer to generate the flashes. But only 15 cd, much less than a Nichia.
I wonder how it works, an IC integrated in the LED?

Yep, there is a small timer circuit in the LED. I've seen these used in red LEDs a long time ago. For a simple, bright flashing light, I've seen people use these low power blinking LEDs with a transistor to switch power to high-power LEDs.

Everyone has different priorities, but I've always been fond of the trusty LM555 when building my own flashing bike taillights. Haven't made one of these in a while, and am happily using commercially built flashing taillights right now.

regards,
Steve K.

 

[TONY M]

I agree with greenLED that the PB superflash is an excellent light and a must have.

 

[Cemoi]

Yep, there is a small timer circuit in the LED.

How does it affect the other elements in the circuit? What happens if you connect this flashing LED in series with a normal LED, will they both flash?

greenLED and Tony: I have a Superflash and I am extremely pleased with it.
My point here was not to inquire about commercial lights, but to know how this flashing LED works, and how to use it in a DIY project.

Maybe I should have started this thread in the LED forum or in the electronics forum? If a mod reads this: please feel free to move this thread to a more appropriate forum, thanks.

 

[greenLED]

greenLED and Tony: I have a Superflash and I am extremely pleased with it.
My point here was not to inquire about commercial lights, but to know how this flashing LED works, and how to use it in a DIY project.

Maybe I should have started this thread in the LED forum or in the electronics forum?

Ah, got it. Yup, Custom and Modified may also get some more DIY-type answers.

Good luck with your project!

 

[Steve K]

How does it affect the other elements in the circuit? What happens if you connect this flashing LED in series with a normal LED, will they both flash?

I've seen this done. You'll still have to limit the current through the flasher, so the second LED will only get as much current as the flashing LED can stand.

You should be able to string a few LEDs in series too, but there will be a limit to the amount of voltage that the flashing LED can control/tolerate.

For more current or voltage, you'll want to use a transistor as a switch.

regards,
Steve K.