OT: Just a thought.

[krw]

No, current_limiting_device == ballast. It does the same thing as an electronic ballast in a fluorescent fixture.

[Josepi]

The efficiency of the ballast circuitry is way up with switching and other modern techniques but still required in any LED circuit.

--------------- In article , m II wrote: LEDs are current devices. Something has to absorb the excess voltage when you control the current supply to it.

[Robatoy]

te:

Ballast =3D inductor (half a transformer... keeping it simple, remember?) NO LED circuit that I have ever seen used in backlit advertising signs has ever included a 'ballast' in the conventional sense. Choppers and resistors and diodes.... I know, all new technology to you... but it is not too late to learn. Now, if you want to burrow into a quagmire of semantics, knock yourself out.

By your logic, if a ship drags an anchor it is 'ballast' as opposed to what 'ballast' really is.

[krw]

That is an example of a ballast, sure. That isn't the definition of a ballast, though.

You couldn't be more wrong. That series resistor *is* a ballast resistor. By "chopper", I assume you mean switching regulator. If it's used to ballast an LED, it's a ballast. ;-)

In case you hadn't forgotten, I'm a electronics design engineer, by day.

Nope. It's common usage.

Perhaps you're a sailor but I'm not claiming to be. I *am* an engineer, though. The widget in series with a lamp to limit current, whatever it may be, is called a "ballast". If it's a resistor, it's even called a "ballast resistor".

[Robatoy]

I have a 1 watt LED and I would like you to give me the part number for a 'ballast' for it.

[krw]

No problem. Give me the part number, the voltage would you like to operate from, and how much current you want through it and I'll give you the part number of a ballast for it.

[Robatoy]

So now you're talking a power supply?

[krw]

I can give you a part number for that too, but you asked for the part number of a ballast for your hypothetical LED. I can't give you that if I don't know its operating conditions.

[Robatoy]

an "electronic

Find me a ballast for LED lighting....sayyyy from these guys:

have them for Fluorescents, and HID, but they use simple power supplies or drivers as they often call them to power LED's. So you're playing semantic ping-pong as per usual. Maybe that engineering degree is a bit long-in-the-tooth and an update is required. In commercial lighting, being it signs or for spaces, the power supplies for LED systems are never referred to as ballasts. Now if there is a resistor in that LED power supply that has a function (although not as an inductor) which acts similar to a ballast, one point for the semantics. End of discussion.

[krw]

Semanitcs? Well, the current limiting resistor in an LED circuit *IS* called a ballast resistor. That's just a fact. That's what a ballast does (limits current).

Nope. I'm still a practicing engineer. Just designed a switching ballast network for an LED (laser diode, actually) today, in fact.

NOT THE POWER SUPPLY! A ballast limits current.

No end of discussion at all. It *IS* a ballast! A ballast doesn't have to be inductive. It can be resistive or capacitive, or switching (mimicking a resistor, capacitor, or inductor). The common principle is that it limits current.

It is semantics, I suppose, because that's what it's called. All words are "semantic".

[Robatoy]

Oh yes it is.

[Bob Martin]

He's right and you're wrong.

[George Watson]

So you say. Troll.

[Stuart]

Very sensible, I've seen the way this guy behaves on other groups.

[Robatoy]

Then you go buy a strip of LEDs to light up a sign and order a 'ballast' for it. You dumb f*ck.

[Robatoy]

Ooops, did *I* say that?

[Swingman]

LOL ... tell what you really think, Rob! ;)

[Han]

Swingman wrote in news:gLmdncTbw6xQG7TTnZ2dnUVZ [e-mail]:

Better done in Dutch, I think, blushing already ... Hope you are doing OK, Rob. Experience and so indicates that the worst mental hump after these things is about 2 months after ...

[Leon]

Potty mouth!

[Robatoy]

I'm sowwy.