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I want to drive APA102 based LED strip from Raspberry Pi, and this strip needs 5V logic level. While I have heard that some people got it working without level shifter or with quick&dirty diode and resistor solutions, I would like to have something solid and stable, which can be plugged into a breadboard for prototyping.

I have read that not all shifters would be good for driving LED strips. For example, TXB0104 might not be suited for this task. Adafruit recommends 74AHCT125. Unfortunately, this chip is hard to find, there are only 74AHCT125D and other variations which will need additional soldering.

Is there any good and reliable and easy-to-find (e-bay or chinese stores) alternative to 74AHCT125, which can be plugged straight into a breadboard and used with LED strip without any additional passive components?

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74HCT241... Or 74HCT541 may be simpler (more efficient pin layout). These chips carry 8 buffers/line drivers instead of 4, and are a bit bigger (I think 20 pins) but I'm guessing they'll be much easier to find. Just make sure to pull the /OE1 and /OE2 lines low if you want the outputs to send one's and zero's (otherwise they'll stay high Z). Ow - You can only get these buffers out of high Z per 4 drivers (but I think that won't be an issue as you're probably fixing all /OE lines to ground anyway)

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You might also consider the 74AHCT245 (the octal version of the quad 74AHCT125). As for where, it depends on where you are. Mouser (for example) ships fast and cheap in the U.S., and the 74AHCT245 seems to be available in various places on ebay as well.

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These are 5V-3V bi-directional level shifters. I've used them both.

https://www.amazon.com/gp/product/B0148BLZGE/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B075PSB71D/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

You might also look into a ULN2003 chip.

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