i2c - Level shifter for multiple voltage levels - Electrical Engineering Stack Exchange
How to Level Shift 1-Wire Systems | Analog Devices
In order to achieve a step-down (5 V → 3.3 V) and step-up (3.3 V → 5 V) level shift (voltage conversion), how should this be achieved? | Toshiba Electronic Devices &
MOSFET level shift - Electronics information from PenguinTutor