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LEDs are simple devices. They have 2 or 3 wires you can connect to. You might be able to control a LED with an I/O pin if it can supply enough current, but I/O pins generally don't provide 220 volts, and, as far as I konw, there is no such thing as a 220 volt LED. Several parts are required to make an interface between 220 volts and an LED.
Why would you want 220V LEDs if you already have logic level digital IO? Just use a transistor and a resistor to drive the LED and drive the transistor from the digital I/O
I know of 220V LEDs, which are mains-operated.
However, I have no experience with such LEDs which allow you to control their blinking rate through a digital I/O pin.
There is no such thing as a 220V LED though. All LEDs work at voltages WELL bellow that, if you have an LED that works on 220V it has a resistor inline with it which drops the rest of the voltage to a safe level so that it can run off the 220V, or some other kind of current limiter.
You didn't answer my question, you have digital I/O control already, why are you trying to power the LED via 220v? Just power it from the digital I/O power supply, which in general should be high enough. Then you just turn the Dgitial I/O line on when you want the LED to be on, so the blinking is all done is software and can be controlled anyway you want.
Yes I was referring to LEDs that come with built-in resistors.
The reason I want to use such LEDs is that I want them to illuminate intensively.
An UC can supply low amount of current which isnt sufficiate for achieving this goal.
ENG, that's why you use current bypass transistors... Either way you in general would NEVER run an LED off 220v's intentionally if you have a lower voltage available, you'd be wasting 99% of the power used by them as heat with a straight resistor, although the capacitive ballast works pretty good.
Hey.
The thing is that I need a quick and dirty solution.
Something that I could just plug into the mains and connect to a digital I/O pin and have it running.
It's just that I'm having trouble with my lawn mower right now. It's beginning to smoke, and I find that all the new lawn mowers are rated in "foot-pounds" at an unknown RPM. I even asked Briggs and Stratton and they replied that they don't know how foot-pounds are related to horsepower!
So I told them the formula and wished them luck on the class action law suit about deceptive labeling practices.
First of all what Digital I/O do you actually have, a micro controller? It has to have a power supply, they're typically 5 volts, or 3.3 volts. If the Digital side is 5 volt powered then you don't need to mess with mains at all you just use the controllers power source and use a simple transistor to drive the LED from the digital I/O line. That's as quick and dirty as you can get. Directly powering an LED from mains is generally not a good idea, at least if you have logic level voltages already at hand.
Hey.
The thing is that I need a quick and dirty solution.
Something that I could just plug into the mains and connect to a digital I/O pin and have it running.
These LEDs usually draw from 1 to 15 Watts depending on what kind of incandescent they are trying to emulate. This is beyond using simplistic Optocoupled Power FETs. However, you can control a small triac with one.
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