I also have an Asante Micro EN/SC designed for PowerBooks, but my guess is it's the same unit with a different design. Mine takes its power from an ADB port, but can also take 5V DC 250mA - ( + from a standard power brick if needed. You shouldn't be far from truth with a 5V brick!

I found that on Google Images:



If it's the same unit than yours, you've got an answer!