PX250 battery modifyJun 6, 2015
Sennheiser PX250 is a noise canceling headphone which shares the similar appearance as PX200. I got it from a friend. He was just about to get a new one since he lost the button of it. I designed and printed the switch to repair it. Later on, I found it was annoying to get AAA x 2 for it all the time. So I decided to modify it a little bit, to replace the battery compartment with a lithium battery and a circuit with the capability of charging, voltage measurement, and regulator.
Basically it suppose to be something like this:
So here was the list of things need to be done:
- Print a new cover to replace the old one (with extra holes for LEDs, the button, and the MicroUSB port).
- Electrodes need to be removed to get more space for circuit and battery.
- The On&Off switch which PX250 uses is EG6201 (made by E switch), which contains 6 switches, one is used for power. You can cut the trace off and place your LDO in between topologically.
- There are two screw holes, which will help to determine the size of the circuit board and the battery.
- Of course, get a battery that just fits in. Design a circuit as well.
New cover 3D modeling
Final assemble. (printed by Makerbot Replicator 2, with helpdisk).