[Andy Brown] wanted one level converter to rule them all, so he set out to build his own which included plenty of options.

The chip at the top and center is a pretty neat little device. It’s an NXP 74ALVC164245DL. In addition to having an incredibly long and seemingly meaningless part number, it contains a pair of bi-directional octal ports. It runs very fast (about 333 MHz) and supports voltages up to 5V on one side, and up to 3.3V on the other. As long as you stay below those maximums you can choose your own target voltages. To do so, he included a couple of adjustable voltage LDOs which are set using jumpers.

But wait, [Andy’s] not finished quite yet. If the jumpers don’t offer the target voltage you’re looking for he also included breakout pins so that you may inject the voltage using an external source. He even included the option to use the LDOs on their own, without the level converter. How do you keep all of these configurations straight? He build a little web form that lets you set your desired parameters and it tells you which jumper should be connected.