Sorry for the elemental question but I'm looking to control a traffic-light-like array of 3 sets of 4 LEDs (one set for each of red, amber, and green). I have the IOWarrior 40 starter kit and each pin obviously has enough power to drive one LED but I'm not sure about 4.
1. Can 4 LEDs in parallel (superbright white/blue, assuming a draw of between 20-35 mA per) be powered from one output pin of the IOW40 starter kit?
2. Assuming #1 is "No", what specs should I look for in transistors to attach to the IOW40 outputs? I'm using the Datasheet section 8.4.1 as a guide and understand the nature of the circuit required but if anyone has used specific components in the past I'd love some pointers.
3. What about a relay & diode for the circuit mentioned in the Datasheet 8.4.2 to control a UK mains current? I know mains power is dangerous, etc., so would rather copy something that somebody else has working.
Thanks in advance.
Which relay for small LED array? UK mains?
Moderator: Guido Körber
For the mains power switches I was also thinking of just ripping apart the remote control to a set like this:
http://www.maplin.co.uk/Module.aspx?Mod ... 1&doy=15m6
...and hooking up the IOW outputs to the remote control. Depends on the inputs (of the remote control) being simple enough and the correct diodes/opto isolator circuits between the IOW and the switch, of course.
http://www.maplin.co.uk/Module.aspx?Mod ... 1&doy=15m6
...and hooking up the IOW outputs to the remote control. Depends on the inputs (of the remote control) being simple enough and the correct diodes/opto isolator circuits between the IOW and the switch, of course.
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Guido Körber
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The current rating for the pins of the IO-Warrior can be found in the data sheet. But it is not sufficent to drive 4 LEDs on each port.
For driving the LEDs you can use some standard transistor like a BC307. Just make sure you put the LEDs in parallel with each having its own series resistor. If you try to use a single resistor you will end up with just one LED working.
Switching mains power direct is not advisable if you have to ask how to do it. This requires certain training and skills without which it is a very dangerous thing.
Using the remote control should be no big problem. Though I don't know the circuit of the transmitter but it is likely you can connect the button circuit direct to the IO-Warrior.
For driving the LEDs you can use some standard transistor like a BC307. Just make sure you put the LEDs in parallel with each having its own series resistor. If you try to use a single resistor you will end up with just one LED working.
Switching mains power direct is not advisable if you have to ask how to do it. This requires certain training and skills without which it is a very dangerous thing.
Using the remote control should be no big problem. Though I don't know the circuit of the transmitter but it is likely you can connect the button circuit direct to the IO-Warrior.