how many led's can u use with a 555/556

[Vizier87]

yeah multisim from electronics workbench i think, i cant get to grips with it.

Of course you can use it. But simulating blinking LEDs? The best thing is to play around with 555 on a breadboard until you get the connections right, and build it after you manage to grip the concept. That is if you want to stick with 555.

To the wiser: The road to circuit-building is quite far from circuit schematics themselves. Assemble, test,test,test. Start with a blinking LED project using 555 on the net, and the rest will come.

 

[ghostman11]

between 100-200, after long chat with the kids the plan now is to have diff kinds of patterns and triggers etc like incorporating a light sensitive resistor and ntc, maybe have a selector switch to swap in and out diff circuits for diff effects.
like i say its only real purpose is a fun way for us to learn a few things. i am open to suggestions on what kind of circuits and effects to use for it, with one proviso....at this stage we want to keep away from pic's and that kind of thing............unless

 

[Vizier87]

The cheap Chinese LEDs have no datasheet and appear to have a very narrow angle. If they do not point directly at you then you won't see them.

Agreed. If you already bought 'em wrap those abominations with some cellophane tape.. that should disperse the light.

 

[Vizier87]

between 100-200, after long chat with the kids the plan now is to have diff kinds of patterns and triggers etc like incorporating a light sensitive resistor and ntc, maybe have a selector switch to swap in and out diff circuits for diff effects.
like i say its only real purpose is a fun way for us to learn a few things. i am open to suggestions on what kind of circuits and effects to use for it, with one proviso....at this stage we want to keep away from pic's and that kind of thing............unless

Seems you're really having a great time with your kids.
Well.... I'd still stick to the 555 timer. For an LDR and NTC conditioning, you can explore op-amps like the LM358 in comparator mode, so if the temp or brightness goes to certain level, the systems goes ON/OFF. If you're going on analog control, like blinking speed versus temp/brightness, I'd have to say PICs are simpler and better suited for that purpose.
Tell your kids they better be prepared for an electronics course.

 

[ghostman11]

lol the kids are realy getting into it!! my nine year old boy is really up for it and i am having fun while i learn. long term plan is the development of our incubators but first i need to learn the basics. i will deff have a play around with all the stuff when it arrives but untill then i have to settle for reading up on stuff and asking question

 

[ghostman11]

ok have the chicken wire frame done!! just need to paper mache it all now , did i mention we want a 3foot model snowman not a 2D one

 

[Sceadwian]

Many users here use LTspice for simulation and Eagle PCB for PCB layout, because they're both free. Their learning curves are a little higher for new users because their user interfaces aren't as well polished and they don't have such pretty graphic visualizations but they're both fully featured.

 

[ghostman11]

cheers sceadwian for that, i will go track down a copy, i have been lent proteus6 on a laptop but seems a nightmare, i try to put a design in isis but even tho it has the chips i want they dont seem to have all the pins on the chips.

 

[Sceadwian]

LTSpice doesn't have a wide range of IC's to work with, there are models for things like linear regulators timers and logic gates, but you won't find a lot of advanced IC simulation in it like micro controllers or anything.

 

[ghostman11]

i have spent the last 16hrs!! getting to grips with proteus, there are a few things that bug me with it but i am starting to get the hang of it SLOWLYYYYYY