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3v to 5v logic converter and power requirements

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MadMisha
(@madmisha)
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I would like some recommendations on a small PCB based 3 volt to 5 volt logic converter. I would also like to know how to power the longer strip of LEDs properly. The product stated that the end of the strip has a connector to power from both ends or extend (I will be running this about 24'[7.32m]). Could I send the same 5V to both sides safely? I would think so but I'm worried that a voltage drop would cause issues. I am also considering a buck boost converter to bump up the 5V to the ESP32 to 6 or 10V. I'm not sure that is needed but since I am using the VIN pin as input, it is better to feed higher power and get the current draw down so as not to dissipate more heat in the onboard regulator (I have seen recommendations and tests, but I'm really not sure on this one).

 

The project:

I have a raised bed with some storage underneath. Now I have a new kitten that also has a bed down there (safe space for him away from people and the dog, he is only 7 weeks old, black and hard to see when we give him his medication). My project is to put individually addressable LEDs controlled by an ESP32 over WIFI that ring the inside of the underside of the bed to see the storage and possible be used as a low light, nightlight (there is the possibility to add a photo sensor and motion detection so that it comes up slowly to a low level at night when we get up but not blind us, possibly red like we had in the fire department to not wake us up or hurt our eyes).

 

Here is my setup:

ESP32: One of the random ones I've had around, I have a few for playing around.

LEDs: WS2812B 16.4, 60px/m 300px (1.5 of them) I went IP65 because they are covered but the IP67 did not have the length I needed and no adhesive although I have really good double stick tape that I use at work.

Power: DC 5V 150W Power supply This is to power the LEDs and the Arduino. Any suggestions on covering the side with the screw terminals better would be appreciated, but I might be overthinking it. I might be able to 3D print something but I haven't printed in over a year or two. Not sure if I want to break it out for this one project, but I also really want to keep the kitten safe.

Case: Arduino Case I plan on cutting holes for the cables and strain relieving them. I do not know how much ventilation an ESP32 really needs. I might cut vent holes. I would love to hear some of your opinions on this as well. My other designs, I had 3D printed cases that I designed and I did include vents but I never really knew if they were needed.

 

Any help would be greatly appreciated. Also, anything that I didn't think of or suggestions would help.

 

Update: I am also looking at aluminum LED channels that place them at a 45 degree angle. Better angles, maybe. I get the LEDs delivered today so I will experiment first.


   
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Ron
 Ron
(@zander)
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Joined: 4 years ago
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@madmisha Hi, I have 3 of those LED strips in my RV I mounted in the pantry, under the sink and around the kitchen island. The LEDS use 12V, that is what I have in abundance. I then use a LM2596 to drop the voltage to between 7 and 8 to apply to the ESP32 or in one case an Arduino ProMicro. They both have internal regulators to get the voltage down the 3.3 they use.

NO you can't send the 5V to both ends. Also, I see your LEDS are 5V, mine are 12V. For your LED power use a medium sized USB wall wart. Your LEDS need 15W according to your link.

I don't know why you think you need 150W, that 10x too big.

2 of my 3 strips are controlled by mag switches through a mosfet module, the 3rd is radar controlled through a mosfet module. In my case the module gets wired to 12V in and out and the gate is triggered by an esp32 pin, pretty simple. There is a dropping resistor on the home made mosfet module to get the 12V down to gate voltage but the 2 store bough don't need it, it's internal I guess.

First computer 1959. Retired from my own computer company 2004.
Hardware - Expert in 1401, and 360, fairly knowledge in PC plus numerous MPU's and MCU's
Major Languages - Machine language, 360 Macro Assembler, Intel Assembler, PL/I and PL1, Pascal, Basic, C plus numerous job control and scripting languages.
My personal scorecard is now 1 PC hardware fix (circa 1982), 1 open source fix (at age 82), and 2 zero day bugs in a major OS.


   
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Will
 Will
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Posted by: @madmisha

Could I send the same 5V to both sides safely?

Yes, to clarify, you can feed both ends of the strip from the SAME 5V power source, but you can't use different sources at each end. 

Anything seems possible when you don't know what you're talking about.


   
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MadMisha
(@madmisha)
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Joined: 4 years ago
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@zander 

I went with the 150W power supply because the manufacturer, as well as reviews, recommended 100W for one roll. I am extending it beyond one roll. I also ordered a very pixel dense strip because I plan on doing some color chases with it. I ordered the Black PCB IP65 16.4ft 300LEDs (x2 , will be cut down). Looking at it now, they are really power hungry. Their math checks out, assuming the power rating per LED is accurate.

LEDRoll2

It looks like they rounded up/left a small cushion, that's what I would have done anyways. I should also take into account that there will be a voltage drop over that 24'.

 

This is the part that confuses me.

LEDRoll

The added voltage. It makes it sound like you can power it from both sides. I went with this brand because of what I wanted to do and fairly good reviews, but the broken English makes it a little confusing. They should arrive today so I can do some testing. There could be a diode there and only allows the voltage to extend to the next strip, but it would make more sense to do that on the connector and not even hook it to the flex PCB.

 

I forgot to mention it, but I also got a few short connectors/wire so that I can do whatever I needed to do.


   
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MadMisha
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Posted by: @will
Posted by: @madmisha

Could I send the same 5V to both sides safely?

Yes, to clarify, you can feed both ends of the strip from the SAME 5V power source, but you can't use different sources at each end. 

Ok, thank you. That was what it sounded like but I was unsure. I would never power it with 2 different power sources. And now that I think of it, I will check to be sure that the output terminals are in fact parallel before doing so. I doubt it wouldn't be.


   
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Will
 Will
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@madmisha 

Good to see you back, it's been a long time.

Anything seems possible when you don't know what you're talking about.


   
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Ron
 Ron
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@madmisha All I know is my strip is 300 LEDS that uses 15W powered with 12V. I do see where your instructions actually call for more voltage to be added every 5M. Never heard of such a thing. Good luck.

First computer 1959. Retired from my own computer company 2004.
Hardware - Expert in 1401, and 360, fairly knowledge in PC plus numerous MPU's and MCU's
Major Languages - Machine language, 360 Macro Assembler, Intel Assembler, PL/I and PL1, Pascal, Basic, C plus numerous job control and scripting languages.
My personal scorecard is now 1 PC hardware fix (circa 1982), 1 open source fix (at age 82), and 2 zero day bugs in a major OS.


   
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MadMisha
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Joined: 4 years ago
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@will 

 

Yeah, good to be back. I've been working so much that I haven't had any time to play around with electronics. Now I feel really rusty and doubt everything. I swear, everything is easier at 120 to 480 volts. That's where I'm comfortable.

 

I'm just surprised that not much has changed in the small electronics maker space since I stepped out. There is a new Raspberry Pi micro but my old go to (ESP32) is still preferable. Maybe I'll see the need for it later.


   
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MadMisha
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@zander 

Are they WS2812 with 5050rgb chips? I have a few of the regular separate RGBW channel ones and they do run much lower power. For this project, I really wanted to do pixel mapping, since I do that at work. This might also be converted to DMX addressing/control later. I am also taking a gamble on not having a white or amber channel. I might not get the colors I truly want. I will have to play around with it to find out. But I do know that I need all 3 LEDs lit to get a white and so I am planning on using full power requirements.


   
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Will
 Will
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@zander 

To clarify, the WS2812B LEDs are RGB LEDS and each colour runs up to 20 ma.

So the total current required is draw/colour times number of colours times number of LEDs in the strip. This means 20 ma x 3 colours x 300 LEDS/5m strip = 18 A maximum power per strip.

Running from 5V means that 5 x 18 = 90 Watts are required for each 5m strip. That's how much it takes to light all of them up as white light at full power. He'll probably wind up using them far below the 60 ma because he won't need (or want) the full brightness.

Anything seems possible when you don't know what you're talking about.


   
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MadMisha
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Posted by: @will

He'll probably wind up using them far below the 60 ma because he won't need (or want) the full brightness.

Nah, stick a Binford sticker on it and blast it!

 

Actually...your probably right, I don't need a blind kitten.


   
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Ron
 Ron
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@madmisha I have both but so far only connected the white leds, the addressable coloured are in the input queue. I figured there would be a difference, but from 15 to 150 seemed extreme. 

First computer 1959. Retired from my own computer company 2004.
Hardware - Expert in 1401, and 360, fairly knowledge in PC plus numerous MPU's and MCU's
Major Languages - Machine language, 360 Macro Assembler, Intel Assembler, PL/I and PL1, Pascal, Basic, C plus numerous job control and scripting languages.
My personal scorecard is now 1 PC hardware fix (circa 1982), 1 open source fix (at age 82), and 2 zero day bugs in a major OS.


   
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Ron
 Ron
(@zander)
Father of a miniature Wookie
Joined: 4 years ago
Posts: 7435
 

@will Ok, that makes some sense. The most recent strip I hooked up came with a dimmer, I have it barely turned on, them suckers are bright. The colored LEDS are for Xmas lights around the windows so they will be running at pretty much the lowest brightness. They will be driven with some sort of music trigger, not sure yet if it will be a speaker and mic arrangement or just voltage from the audio waveform.

First computer 1959. Retired from my own computer company 2004.
Hardware - Expert in 1401, and 360, fairly knowledge in PC plus numerous MPU's and MCU's
Major Languages - Machine language, 360 Macro Assembler, Intel Assembler, PL/I and PL1, Pascal, Basic, C plus numerous job control and scripting languages.
My personal scorecard is now 1 PC hardware fix (circa 1982), 1 open source fix (at age 82), and 2 zero day bugs in a major OS.


   
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Will
 Will
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Posted by: @madmisha

Actually...your probably right, I don't need a blind kitten.

It's a cat, it doesn't need much light to start with 🙂

Anything seems possible when you don't know what you're talking about.


   
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Ron
 Ron
(@zander)
Father of a miniature Wookie
Joined: 4 years ago
Posts: 7435
 

@will If I think of it tomorrow, I will try getting my clamp on ammeter on one of the DC leads to get a amp reading. Since I have the dimmer cranked almost off I don't expect much. BTW Will this morning I saw the radar at work, I had eyes on when the lights turned on. I was 90 degrees to the sensor through at least an inch of wood and some misc stuff in a storage bin. VERY sensitive. 

First computer 1959. Retired from my own computer company 2004.
Hardware - Expert in 1401, and 360, fairly knowledge in PC plus numerous MPU's and MCU's
Major Languages - Machine language, 360 Macro Assembler, Intel Assembler, PL/I and PL1, Pascal, Basic, C plus numerous job control and scripting languages.
My personal scorecard is now 1 PC hardware fix (circa 1982), 1 open source fix (at age 82), and 2 zero day bugs in a major OS.


   
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