Philipp Stenkamp wanted to power his Stellaris Launchpad with a spare LiPo battery, but found as shipped this wasn’t a plug-and-play operation. “The Launchpad expects 4.75-5.25 VDC on VBUS, nothing that a single cell LiPo could provide. I know that the system voltage is 3.3 VDC and that the voltage regulator on the board has a very low dropout voltage, so powering the Launchpad with anything between 3.4-5.25 VDC should work well. The voltage of a single-cell LiPo ranges between 3.0-4.2 VDC, so let’s populate this header and plug a fully charged LiPo in it! Being a practical guy, I did just that. Guess what, nothing happened!” With a little research he discovered the way to making the Launchpad LiPo friendly was as simple as cutting a trace.
Visit Philipp’s webpage for project background and details on the risks and benefits of this hack.