Do You Even Need A Level Shifter? It might seem odd ... when you first have to ensure that different logic levels are safely interfaced. Will my 5V Arduino harm this 3.3V sensor?

For UART data level shifting, 74AVC4T245FT has four bidirectional level shift circuits in two pairs ... output-enable pins are within the ‘A’ side voltage domain and their logic levels are ~30% and ...

To aid in this task, [Jan Oelbrandt] created Shift4Me, an open-source Arduino powered electronic shifter. The system consists of a hall effect sensor at the pedals to measure cadence, an Arduino ...