[mrichard629]

I have an old portable dvd player. It still holds a charge which is fantastic. I don't use it anymore due to digital video and such. I took it apart this morning to look at the guts (out of curiosity) and I got to thinking. Is there a way to adapt the device to be used as a ups. My desired result. I have a raspberry Pi that will host a small website/database thing. Its power requirements are 5v dc 1000 mah (1a) (max input) it routinely uses less than that in idle. The battery is 7.4v DC 3200 mah (3.2a). Is there a way to to regulate the battery to work with the raspberry pi?

[ebaines]

Yes - you could make up a voltage splitter to drop the 7.4V output to 5V to be used as input to the other device. I think it's a pretty safe bet that the current draw will not exceed the DVD battery's capabilities. However, "mAh" is milliamp-hours, and is a measure of how long the battery can produce a certain level of amperage at its rated voltage before running out of juice. It's not a measure of the current draw requirement for the Raspberry nor the current producing ability of the DVD battery, but again - I doubt that's an issue in this case.

[InfoJunkie4Life]

Using resistors or some sort of voltage regulation circuit you could use the battery to supply the voltage needed.

Here is a link that may fancy your interest:
http://www.circuitstoday.com/3a-switching-regulator
How to Make Your Own Battery Backup Circuit - A Short & Practical Tutorial

[HowHardCanItBe]

I'm not sure about the Raspberry, but I know that the Arduinos have onboard voltage regulators. Most power supplies need regulating, it's likely that it has it. Just would want to make sure that it's not feeding through a terminal meant only for 5v or you'll let the smoke out :)