SongHe 10pcs 4 Channels IIC I2C Logic Level Converter Bi-Directional Module 3.3V to 5V Shifter for Arduino (Pack of 10)

Got items. Looks different from the photo. doesn't work. By testing circuit found out that schematic is wrong. On the photo resistors located from both sides but actually they are on the same site. Don't buy

I seen this pcb circuit they arrange components (transistors and resistors) not correctly

I've used two level converters so far on projects without issue (except too much signal interference prototyping on a breadboard). I've successfully connected 3.3V Raspberry Pi pins to retro 8-bit 5V serial port for bi-directional communications (e.g. file transfer). The uploaded photo shows three of these devices: one still in the ESD bag, another wire-wrapped and still in test/dev before installing on a new breadboard, a third one between two coins on a solderless breadboard to convey its sizeThese devices saved me from dealing directly with the SMD discrete components and the clearly labeled boards make usage fool-proof. Since my signal rates are low enough, I haven't run into any speed tolerance issues that others have complained about. Each level converter comes packaged within ESD bags along with pin headers (not always needed). I recommend and would buy again.

Price and quality

If you thought you were going to use these for addressable LEDs like WS2812b, NeoPixels, etc., -- think again; they are not fast enough. You want a 74AHCT125 or similar.

No issues from wiring the first one onward. There's not much to say -- make sure you connect the HV, LV, and GNDs, and the signals shift up and down (3v3 <-> 5v) flawlessly so far. Circuit boards are clean and have easy to read pin labels. I used the first one to shift control signals from an ESP8266 (3v3) to WS2812b (5v) lights.This design is nice, as long as you don't need to turn the shifter on/off in software (such as delaying it coming online until a microcontroller has booted), as unlike some other logic shifters, it does not have a pin that needs to be raised high to turn it "on" -- it just needs both sides provided with the appropriate power supplies. For my projects, these are perfect.

I needed to run a lot of Neopixels from a 3.3v NodeMcu and was having some issues, these little guys fixed my problem and were very inexpensive.