Logic Level Conversion

3.3 to/from 5 volts

When the "Low side" (3.3 volt device) is high, mosfet off, "High side" (5 volt device) is at 5 votls via R2. When low, mosfet on, grounding high side. When 5 volt device drives "High side" to 5 volts, mosfet source pulled up to 3.3 volts for low side. When low, mosfet is activated via substrate diode, grounding low side.

TTL - RS232 conversion

NEW! RLC-2 RS232 Level Converter in a DB9 backshell

Logic Family Interoperability

The Art of Electronics (Horowitz & Hill, Cambridge University Press, ISBN 0-521-37095-7) On page 574 is a nice little table that lists what you can drive with what.

¹ pullup to +5V, or use HCT as interface.

Archive:

• List post "dual voltage translation (resistors vs IC's)" +

See also:

• http://www.hobbytronics.co.uk/mosfet-voltage-level-converter

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