Activity: Logic Voltage Level Shifting, For ADALM1000 [Analog Devices Wiki]
What's wrong with this single-transistor level-shifter? - Electrical Engineering Stack Exchange
Bi-Directional Level Shifter – HUSSTECH
Level-shifter block sips power - EDN
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 &