Xbox 360 Power Supply Hack

My most recent scooter (that I built and haven't yet blogged about) uses a 7s2p Lithium Iron Phosphate pack using A123 cells. That is great except my Triton EQ charger can only handle 6s Lithium anything. The obvious solution was to purchase new charging equipment like this beautiful Turnigy 8s charger capable of 7A continuous. However, it also means I need to find a suitable power supply that can output at least 4.6A at ~23.1V with an input range of 11 to 15V.

That last requirement removes most laptop power supplies from the list of hopefuls. But, it does shine some light on my favorite gaming platform, the Xbox 360. The 360 variants feature external power supplies with some funky 8 pin output cable. Furthermore there are variants that output some 135W (Xbox 360 Slim) to 203W (Xbox 360 original console) of power. My favorite part about these power supplies is they can be obtained for cheap because they are available everywhere. I grabbed a 150W variant off ebay for $18 free shipping.

Alright! Hacking time! I received my box and noted many familiar items. Wall plug, power brick, lalala... oh wait.

8 pins wtf

What the hell is this? Some 8-pin output connector that goes into the Xbox. No clear labeling on the outside to signify the purpose of the pins.

It turns out, six of the pins are used for power transmission and two are used for a "standby" state. This is probably the minimum power required for the sleeping state on the Xbox (I mean how else do you turn it on using the wireless controllers?). Here is the pinout:

Courtesy of that website. Kudos go to them.

If you were to probe the outputs with a multimeter, you will find a 0V potential between the yellow and black UNTIL you supply the PWR_ENABLE pin with +5V. We are going to simply take the +5V USB line (RED) and connect it to the PWR_ENABLE permanently. Then we will connect the yellow and black wires together in parallel because I don't feel like 22ga PVC jacket wire is ever going to safety transmit 150W.

Anyway, I unplugged the charger cord, and immediately sliced into the cable behind the connector. Conveniently enough, the cables are colored accordingly.

8 pins, 8 wires. Life is good.

Strip away more wire and begin soldering things together. Three BLACK in paralle, three YELLOW in parallel, and connect the BLUE and RED/PURPLE.

Your choice on the shrink wrap and external connector. A good choice might be a power strip in case you want to power multiple items with it. Since this power supply is single duty, I soldered in an XT60 connector used for hobby RC.