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I would like to build a 5v circuit that uses an sd card and a 3.3v SPI screen and for the level shifting I would like to use the common mosfet circuit, but all versions I have seen use a BSS138 which comes just in surface mount format.

Are there other alternatives to this mosfet that come in through hole format? like TO-92 format?

I was thinking of using a BS-170, is it ok for my use?

Note: The SPI clock will be 8 MHz

The circuit I'll be using (Source sparkfun's level shifting tutorial)

The circuit I'll be using (Source sparkfun's level shifting tutorial)

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    https://electronics.stackexchange.com/questions/18457/is-my-mosfet-based-bidirectional-level-shifter-insane?rq=1 Russell McMahon provides an excellent description of how this circuit works, and what to look for in a MOSFET for it. – Colin Jan 10 '18 at 16:11
  • Great link @Colin__s, thanks for that! I forgot all about that answer. – DerStrom8 Jan 10 '18 at 16:16
  • Sadly the alternative he provides is not available with the provider I'm buying from. Are there other alternatives? (Edit) wait, it is available, the search engine just lied to me lol. Thanks for the link –  Jan 10 '18 at 16:37
  • Does this signal really need to be bi-directional? – Trevor_G Jan 10 '18 at 17:09
  • No it doesn't, but is the simplest circuit I could find, as with other options I would need to have 2 different IC, one for the 5v to 3.3v signals and the other ic for the signals coming back. –  Jan 10 '18 at 17:33
  • Why not just use a 74'245? It's kind of what it was designed to solve. See for instance the data-sheet of SN74AHCT245. – Pål-Kristian Engstad Jan 10 '18 at 20:00
  • Maybe it's time to try dealing with trivial surface mount packages, like those having only 3 leads? Or you can buy 4-channel versions of this circuit already assembled on a small board, likely with footprints for breadboard compatible pin headers on each end. – Chris Stratton Jan 10 '18 at 21:09

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