# Capacitors... One per output, or just one on the input?

**URL:** <https://wled.discourse.group/t/capacitors-one-per-output-or-just-one-on-the-input/4010>\
**Category:** Hardware\
**Created:** [November 13, 2021, 1:52am UTC](https://wled.discourse.group/t/capacitors-one-per-output-or-just-one-on-the-input/4010 "2021-11-13T01:52:22Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![lxkev](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/lxkev/32/10064_2.png) [@lxkev](https://wled.discourse.group/u/lxkev)\
**Post date:** [November 13, 2021, 1:52am UTC](https://wled.discourse.group/t/capacitors-one-per-output-or-just-one-on-the-input/4010/1 "2021-11-13T01:52:22Z")

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Just Wiring up a wemos D1 pro with a two-channel level shifter.

I’m planning to use two-pin outputs.

Can I just put 1 capacitor on the input side, or do I need a capacitor per output…

Basing this on the below… I’m assuming if I Just put the capacitor across the power in… it will do the job?

 ![](https://global.discourse-cdn.com/free1/uploads/wled/original/2X/9/98590521b32308caa7c65aa33b5b1fd85de813de.png)

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**Author:** ![tonyno](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/tonyno/32/242_2.png) [@tonyno](https://wled.discourse.group/u/tonyno)\
**Post date:** [November 13, 2021, 1:37pm UTC](https://wled.discourse.group/t/capacitors-one-per-output-or-just-one-on-the-input/4010/2 "2021-11-13T13:37:07Z")

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The cap should be for each strip at each strip.

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<div class="post-metadata">

**Author:** ![lxkev](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/lxkev/32/10064_2.png) [@lxkev](https://wled.discourse.group/u/lxkev)\
**Post date:** [November 14, 2021, 8:28am UTC](https://wled.discourse.group/t/capacitors-one-per-output-or-just-one-on-the-input/4010/3 "2021-11-14T08:28:30Z")

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Why?

If a capacitor is in parallel on the power supply line wont it do the same thing?

Also should you add a capacitor before power injection?

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<div class="post-metadata">

**Author:** ![tonyno](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/tonyno/32/242_2.png) [@tonyno](https://wled.discourse.group/u/tonyno)\
**Post date:** [November 14, 2021, 12:56pm UTC](https://wled.discourse.group/t/capacitors-one-per-output-or-just-one-on-the-input/4010/4 "2021-11-14T12:56:07Z")

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The idea is that it acts as a buffer for the LEDs, so should be close to them.

> **[Adafruit NeoPixel Überguide](https://learn.adafruit.com/adafruit-neopixel-uberguide)**
>
> NeoPixels are “intelligent” full-color RGB LEDs that can be controlled and chained from a single microcontroller pin. This guide presents an overview of NeoPixel products, along with tips for building and powering projects of all shapes and sizes.