# do parallel connected leds consume more power?

Discussion in 'LEDs and Optoelectronics' started by rahulb, Nov 8, 2018.

1. ### rahulb

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Hi,

I wanted to know if leds which are connected in parallel to power source consumes more power than leds connected in series?

I read somewhere that leds in series consume less power.

thanks

rahulb, Nov 8, 2018
2. ### hevans1944Hop - AC8NS

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Each LED will consume an amount of power equal to its forward voltage drop at whatever current is passing through the LED. If you connect LEDs in parallel, there is no way to guarantee that each will have the same forward voltage drop, nor that the current will distribute equally across all the LEDs connected in parallel.

If you want to connect LEDs "in parallel" place a current-limiting resistor in series with each LED, then wire as many of these resistor/LED series combinations in parallel with each other as desired. Again, the power dissipated will be the forward voltage drop across a given LED multiplied by the current through that LED.

You do the math. Relying on "glittering generalizations" such as "leds in series consume less power" will only mislead you, and such statements serve no useful purpose. Learn about electricity, Ohm's Law, Kirchoff's Current and Voltage Laws so you can participate meaningfully on this forum.

hevans1944, Nov 9, 2018
(*steve*) likes this.
3. ### (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

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I agree. The LEDs (properly driven) will consume the same amount of power no matter how you connect them.

It's the rest of the circuit that you need to look closely at.

For a given voltage power supply, and if you use only linear elements to set the current through the LEDs, then a series connection is more efficient. However, there may be other considerations, and other forms of driving the LEDs that may change things.

Last edited: Nov 9, 2018
(*steve*), Nov 9, 2018

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