# How do I know if I need a level shifter? **URL:** \ **Category:** Questions\ **Created:** [November 9, 2020, 1:52pm UTC](https://wled.discourse.group/t/how-do-i-know-if-i-need-a-level-shifter/1267 "2020-11-09T13:52:03Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![MikeRuddy](https://avatars.discourse-cdn.com/v4/letter/m/f1d935/32.png) [@MikeRuddy](https://wled.discourse.group/u/MikeRuddy)\ **Post date:** [November 9, 2020, 1:52pm UTC](https://wled.discourse.group/t/how-do-i-know-if-i-need-a-level-shifter/1267/1 "2020-11-09T13:52:03Z")
The wiki says: > _If this wire cannot be kept short, use a level shifter/translator._ Optionally connect a normally open pushbutton to `GPIO0` (NodeMCU/Wemos pin `D3` ) and ground. How do I know how “short” it needs to be? I am planning on using a separate [12V 30A power supply](https://www.amazon.com/gp/product/B01EWG6YT8/ref=ppx_od_dt_b_asin_title_s00?ie=UTF8&psc=1) to run my [500 WS2811 12V LEDs](https://www.amazon.com/gp/product/B01MCQP7KP/ref=ppx_od_dt_b_asin_title_s00?ie=UTF8&psc=1) and I’ll power a ESP32 D1 mini using a 5V USB Micro cable and brick. I am interested to hear how “connecting a normally open pushbutton to `GPIO0` (NodeMCU/Wemos pin `D3` ) and ground.” helps here vs. using a level shifter. Also if I just hook it up without a level shifter do I still need to use a 470Ohm resistor as described in the diagram here: ![Screen Shot 2020-11-09 at 8.50.23 AM](https://global.discourse-cdn.com/free1/uploads/wled/original/1X/edc73b9be7f613459af111f60b3459be052d14cd.jpeg) Thanks for your help, -Mike ---
**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 9, 2020, 2:28pm UTC](https://wled.discourse.group/t/how-do-i-know-if-i-need-a-level-shifter/1267/2 "2020-11-09T14:28:20Z")
Short is under a few inches (8cm). The button is not related to the level-shifter. 😉 ---
**Author:** ![huggy-d1](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/huggy-d1/32/51_2.png) [@huggy-d1](https://wled.discourse.group/u/huggy-d1)\ **Post date:** [November 9, 2020, 4:12pm UTC](https://wled.discourse.group/t/how-do-i-know-if-i-need-a-level-shifter/1267/3 "2020-11-09T16:12:45Z")
There are too many unique GND’s in your posted image. The 12V and 5V supply GND lines need to be interconnected. Otherwise, things will make you unhappy immediately, or eventually (within a short period of time after starting an effect). Once the difference in voltage between the 2 GNDs is significant, the data signal will appear weaker to the LED strip, or too strong. Too strong may burn out the first LED. Too weak and the first LED may never accept any of the data signals. ---
**Author:** ![MikeRuddy](https://avatars.discourse-cdn.com/v4/letter/m/f1d935/32.png) [@MikeRuddy](https://wled.discourse.group/u/MikeRuddy)\ **Post date:** [November 9, 2020, 6:06pm UTC](https://wled.discourse.group/t/how-do-i-know-if-i-need-a-level-shifter/1267/4 "2020-11-09T18:06:52Z")
Hi Huggy, I grabbed that image from the wiki: [https://github.com/Aircoookie/WLED/wiki](https://github.com/Aircoookie/WLED/wiki) Can I use a buck converter (such as [https://www.amazon.com/gp/product/B00J3MHRNO/ref=ppx\_od\_dt\_b\_asin\_title\_s00?ie=UTF8&psc=1](https://www.amazon.com/gp/product/B00J3MHRNO/ref=ppx_od_dt_b_asin_title_s00?ie=UTF8&psc=1)) to go from my 12V power supply to my 5V ESP32 w/o needing to use a _level shifter/translator_ and have them use the same ground from the 12V PSU? ---
**Author:** ![huggy-d1](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/huggy-d1/32/51_2.png) [@huggy-d1](https://wled.discourse.group/u/huggy-d1)\ **Post date:** [November 9, 2020, 6:18pm UTC](https://wled.discourse.group/t/how-do-i-know-if-i-need-a-level-shifter/1267/5 "2020-11-09T18:18:25Z")
The simple solution is to run a wire from the GND wires of the 2 power supplies. Less simple but equally useful is to use a WAGO style connector to jumper all the GND wires together. Something similar to this: [https://www.wago.com/us/wire-splicing-connectors/compact-splicing-connector/p/221-415](https://www.wago.com/us/wire-splicing-connectors/compact-splicing-connector/p/221-415) 5V supply GND, 12V GND, ESP32 D1 Mini GND, Level Shifter GND, LED Strip GND (5 wires) And in an ideal world, the wall outlet GND wire to the 0V/GND of both supplies should be connected together as well. Otherwise, the 0V / GND of the entire system could develop a voltage to ground, and when anyone touches anything grounded in the system, ESD could cause damage. ---
**Author:** ![srg74](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/srg74/32/3018_2.png) [@srg74](https://wled.discourse.group/u/srg74)\ **Post date:** [November 9, 2020, 10:45pm UTC](https://wled.discourse.group/t/how-do-i-know-if-i-need-a-level-shifter/1267/6 "2020-11-09T22:45:42Z")
Look at this project [https://github.com/srg74/WLED-wemos-shield](https://github.com/srg74/WLED-wemos-shield) ---
**Author:** ![Modelman](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/modelman/32/416_2.png) [@Modelman](https://wled.discourse.group/u/Modelman)\ **Post date:** [November 10, 2020, 12:49pm UTC](https://wled.discourse.group/t/how-do-i-know-if-i-need-a-level-shifter/1267/7 "2020-11-10T12:49:09Z")
A quick 15 min diode level shifter hack for the Peace Penguin Alpha mod. It worked great while I was waiting for a QuinLED-Dig-Quad setup. A 330R resister can be added to the pixel data output for more stability. I was able to achieve non flicker runs of over 5m. ![IMG_20201110_123042](https://global.discourse-cdn.com/free1/uploads/wled/original/1X/4127d5455c1f002762edf6f6ecff1d4034b9f7d1.jpeg) ![IMG_20201110_122947](https://global.discourse-cdn.com/free1/uploads/wled/original/1X/99ca490727ae7397db3f6f4ff93e502a5cba192f.jpeg) ---
**Author:** ![AshleyF](https://avatars.discourse-cdn.com/v4/letter/a/51bf81/32.png) [@AshleyF](https://wled.discourse.group/u/AshleyF)\ **Post date:** [March 31, 2023, 9:13pm UTC](https://wled.discourse.group/t/how-do-i-know-if-i-need-a-level-shifter/1267/8 "2023-03-31T21:13:22Z")
Is linking all the GNDS a very thing to do? I have my 12v psu powering the strips and a 12v-5v board. 12v-5v board then powers the esp 8266. So the GND’s from the strips, psu and 12v-5v board are all joined but not the GND from the esp8266. Is this ok or will linking the esp8266 GND in aswell help out the setup. It all seems to work fine apart from a bit of volt drop on my furthest strip, (6m away from esp/psu) power injector going in tomorrow. Data line seems fine at 6m and I don’t have a level shifter, ( I take it one would help?) ---
**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:** [April 3, 2023, 4:28pm UTC](https://wled.discourse.group/t/how-do-i-know-if-i-need-a-level-shifter/1267/9 "2023-04-03T16:28:45Z")
Yes, if running LEDs at \>5V you will most-likely need a shifter. Keep in mind that the ESP puts out 3.3v signals and LEDs need 5v.