Ok, so basicly i got this circuit from LED keychain that houses 2 3mm leds, resistor, on off switch, and it obtains power from 1 cd2025 flat battery. what id like to do is modify this curcuit board to operate from 4x aa or aaa battery box i stole from my sons broken down toy and upgrade the circuit to power up 8x LED 5mm. I got wires, soldering iron and soldering, shrinking tubes and all, but do i need some other parts or can i just weld out thebatterybox, cut the wires of leds and extend it those with wires to 2x4 set of LEDs. leds are paralel and in serie. what else i need to know if i do this? plan was to use it as a circuit inside my airsoft mask, that would hold the switch on the side, that also houses the circuit board, and inside is the battery box.
led's only have 2 things to think about.. voltage and polarity (current as well but that just affects battery life in any way that matters). how were the pair connected in the original unit.. series or parallel? I would guess parallel seeing as there is 3v available and 3v is a common led voltage. If you get 3v led's and you have 6v available from battery box make them up into 4 lots of series connected pairs, anode to cathode.. Simple things really, just like a bulb with a polarity.. makers spec sheets will tell you the needed volatge and any possible ballast resistor required. They make an evil smell if you burn them out on too much volts as well..
Thanx, what i figured is, that if i put set of 3s it makes 9 volts demand right? so pairing em 3x2 would need 9 volts. so instead of using AA batteries, i could go using 9v battery (those block looking ones) and put 2 of em in paralel to extend lifetime of battery, would make also planning the chip easier. in original chip they were paralel (1+1), but i am gonna extend that chip to house 2 led series with 3 in each (oh right, modified the plan from 8led to 6 led) in paralel. p.s. did you knew this? Red or Orange 2.0 V Yellow 2.1 V Green 2.2 V True Green, Blue, White 3.3 V Blue (430 nm) 4.6 V Read more: How to Design a Simple LED Circuit | eHow.com http://www.ehow.com/how_4836713_design-simple-led-circuit.html#ixzz1sVQZyPiE and at this point, i think i am gonna build my own circuit instead...