Source for single channel 5v Logic Level Shifter?

Hi All!
I’m working on some wled projects where space is a very limited resource.
I have a pretty small 4x 5v logic level shifter, but really only need the one.
image

Does anyone have a source for just a single line unit? Why are they so hard to find?

Sorry if this is an ultra-noob question. I’m ultra-noo

This Transistor based Levelshifter are crap! :nauseated_face: Cause they are very slowly. Use 74LVC1T45. SOT26 should small enough :wink:
Aviable by good distributors. I order in most cases from LCSC
https://www.lcsc.com/product-detail/Translators-Level-Shifters_Diodes-Incorporated-74LVC1T45W6-7_C168856.html

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100% do not use that level shifter!!

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Ohh this is plenty small! Thank you so very much!

Are you familiar with datasheets? In a recent project I’d use this levelshifter. Here is a link, with schematic.
https://wled.discourse.group/t/once-more-esp8266-based-wled-controller/11130
:wink:

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I used it once and it seemed to work ok… what sort of behavior would I see due to this transistor slowness?
This is academic, though. I’ve ordered 25 of the 74LVC1T45 :slight_smile:

The transistor solution is ok for a UART or a I2C sensor, with no much speed. But a WS2812 telgram needs roundabout 400 Khz clockspeed. It can work, but not pretty good. If it doesn’t work or be unstable, without oscilloscope you will be without cance :tired_face:
A real levelshifter is 10 times faster and can drive higher output loads, what will result to can use longer distances for dataline, cause a dataline is a small parasitic capacitor to ground. Longer line will increase the capcity. Every time when level switched, the capacitor will change his polarity. This is like a brake for the signal :wink:

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They are generally too slow for addressable LEDs. It also says to not use them in the KB

“Warning
I2C shifters are generally too slow for addressable LEDs, so don’t use them.”

Further info: Levelshifter Analysis

It has also been said in just about every topic in the forums that talk about level shifters to not use the I2C ones.

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74LVC1T45 is not TTL level so beats the purpose

It doesn’t need to be TTL input compatible as that’s a dual voltage device.
You need to set VccA to 3.3V, VccB to 5V and DIR from A->B to get proper levelshifted data on B.

I’m with you though, there’s much simpler solutions in the same package size:

  • 74AHCT1G32 Single AHCT OR gate
  • 74AHCT1G125 Single AHCT controlled output buffer

Either of those will work just like their 4 gate version big brothers and need only 5V supply.
Much easier to use.

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Ohh, I’ll try these next! How exciting thank you!
And for later me…
Data wire from pwm0 (G18) to pin 2 74AHCT1G125.
74AHCT1G125: 1 and 3 pin to GND , 5 pin to +5V , 4 pin to strip WS2813 pin DI .