Will this circuit work?

tshuck

Joined Oct 18, 2012
3,534
If you are only attempting to light the first LED, yes, but you'll likely burn it out after a short while.

Otherwise, you can stack 2 or 3 LEDs in series (a string of components) with a single resistor across the battery.

Either way, a single LED and a single 270 ohm resistor will take 23mA - exceeding the max current for some LEDs.
 

MaxHeadRoom

Joined Jul 18, 2013
28,619
Actually the battery is shown the right way around, it is the +- notation that is wrong.
The +ve terminal is actually connected to the black wire.
Max.
 

MaxHeadRoom

Joined Jul 18, 2013
28,619
IOW, the circuit should work as shown, the Red conductor customarily goes to the +ve battery terminal.
You have the battery +ve drawn in Black which tends to throw a viewer off at first.
Max.
 

ScottWang

Joined Aug 23, 2012
7,397
What's reason to make you to do the circuit like that, it is not a regular method, you should use led in series with resistor and in parallel all of five leds and resistors strings.
 

Thread Starter

Evie

Joined Mar 11, 2015
9
What's reason to make you to do the circuit like that, it is not a regular method, you should use led in series with resistor and in parallel all of five leds and resistors strings.
the LEDs im going to be using are 2.5v. I will be using 5 of the them which so they will need 12.5 v, but the battery is only 9v?
 

ScottWang

Joined Aug 23, 2012
7,397
the LEDs im going to be using are 2.5v. I will be using 5 of the them which so they will need 12.5 v, but the battery is only 9v?
Using 80% of 25mA for brightness and led life, it will be 20mA.
R=(9V-2.5V)/20mA=325Ω, yous can choosing 330Ω.
You can have 5 strings or two strings as two leds in series with one resistor and three leds in series with one resistor.

You can calculate the R values for two and three led strings.
 

Reloadron

Joined Jan 15, 2015
7,501
Here is what the members are getting at using a series parallel configuration.

LED Series Parallel.png

I would also do as Scott suggest and calculate the series resistors based on 20 mA. My numbers were based on 25 mA. So slightly higher value resistors that conform to off the shelf values.

Ron
 
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