Can i connect an 1.2v LED bulb to a 1.5v D battery(in a battery holder)

Question

i have a 1.2v LED bulb and want to connect it to a 1.5v D battery(using a battery holder). i dont know where to connect each wire, or what to do HELP

Answer 1

If you do that you will have no control over the current whatsoever. If the battery voltage is high (say with a new battery), you will put too much current through the diode. As the voltage drops, the current will drop much faster as the diode has a non-linear current characteristic. That's why this method is never used.

What we do which works much better, is to feed using what is known as current feed. We use a higher voltage and use a series resistor to control the current. If you were to use a 3v (2 cell) battery, you would use a 90 Ohm resistor in series.

With LED's it is normal to mark the cathode with a flat spot (which is usually opposite the long leg which is the anode). The cathode goes to the most negative point in your circuit.

Answer 2

       You will need to wire in a resistor, also. or else it'll discharge battery too fast, or fry LED. a 1500 ohm resistor (1/4 watt) should be about right. just wire your parts in a loop, from plus side of battery, to minus. if it doesn't light, reverse wiring