I want to make a string of 15 3.6v LEDs. I need to drive it with 3 1.2v batteries, but I want to space them out evenly along the circuit. I'm stuck on how to make the circuit because the LED's all have to be run in parallel, but the batteries in series. Is this possible?
The layout would be: battery, 5 leds, battery, 5 leds, battery, 5 leds
Thanks for any help!
[EDIT] Sorry, in hindsight I should have been more clear about what I'm asking, what the project is and why I would consider the above scenario.
I want to power a string of 3.6v, 20mA LEDs using 1.2v batteries that must be placed throughout the circuit. Ideally, using 4 batteries and individual resistors for each LED, the 4 batteries create a combined voltage of 4.8v, so the LEDs must be connected in parallel and the batteries in series. This would allow me to create enough voltage where I can attach a 68 (I think that's the closes to 60) ohm resistor to each LED to reduce the voltage and control current in the circuit.
I know how to make it if all the batteries were in one location, but the 4 batteries need to be evenly distributed throughout the string of LEDs, so that I have: Battery - 4 LEDs - Battery - 4 LEDs - Battery - 4 LEDs - Battery - 4 LEDs (Not shown are the resistors attached to each LED). The project is for a very small diameter, light weight LED hula hoop, so weight distribution is very crucial. I also need to use the lower voltage batteries so that they fit inside the tubing.
My initial strategy was to use only 3 batteries which will 'just' power the LEDs in an attempt to keep the weight as low as possible. I'm using a very small gauge wire and 3mm LEDs to also help compensate for both weight reduction and ability to fit inside the tube. I have made several LED hoops already, all using 2 3v batteries in series, located in 1 place then a string of parallel LEDs following it, each with it's own resistor. Each LED/Resistor combo was soldered to the wire with heat shrink applied around each connection to insulate the exposed wire and add stability.
I'm aware of the implications the 3 battery setup can cause, but I have read up on the "real world" application of using a batteries internal resistance to control the current and in such a minor application such as this I was told that it's most likely it will work just fine.
However, my real issue simply comes down to not knowing how to create a circuit that the batteries are evenly placed along the circuit rather than all in one location, while being able to combine the batteries voltages yet keeping the LEDs in parallel. Is this circuit possible and if so, would anyone be willing to provide me with a wiring diagram?
The layout would be: battery, 5 leds, battery, 5 leds, battery, 5 leds
Thanks for any help!
[EDIT] Sorry, in hindsight I should have been more clear about what I'm asking, what the project is and why I would consider the above scenario.
I want to power a string of 3.6v, 20mA LEDs using 1.2v batteries that must be placed throughout the circuit. Ideally, using 4 batteries and individual resistors for each LED, the 4 batteries create a combined voltage of 4.8v, so the LEDs must be connected in parallel and the batteries in series. This would allow me to create enough voltage where I can attach a 68 (I think that's the closes to 60) ohm resistor to each LED to reduce the voltage and control current in the circuit.
I know how to make it if all the batteries were in one location, but the 4 batteries need to be evenly distributed throughout the string of LEDs, so that I have: Battery - 4 LEDs - Battery - 4 LEDs - Battery - 4 LEDs - Battery - 4 LEDs (Not shown are the resistors attached to each LED). The project is for a very small diameter, light weight LED hula hoop, so weight distribution is very crucial. I also need to use the lower voltage batteries so that they fit inside the tubing.
My initial strategy was to use only 3 batteries which will 'just' power the LEDs in an attempt to keep the weight as low as possible. I'm using a very small gauge wire and 3mm LEDs to also help compensate for both weight reduction and ability to fit inside the tube. I have made several LED hoops already, all using 2 3v batteries in series, located in 1 place then a string of parallel LEDs following it, each with it's own resistor. Each LED/Resistor combo was soldered to the wire with heat shrink applied around each connection to insulate the exposed wire and add stability.
I'm aware of the implications the 3 battery setup can cause, but I have read up on the "real world" application of using a batteries internal resistance to control the current and in such a minor application such as this I was told that it's most likely it will work just fine.
However, my real issue simply comes down to not knowing how to create a circuit that the batteries are evenly placed along the circuit rather than all in one location, while being able to combine the batteries voltages yet keeping the LEDs in parallel. Is this circuit possible and if so, would anyone be willing to provide me with a wiring diagram?
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