Observations about the universe, life, Lausanne and me

Tuesday, March 18, 2008

DIY Nokia USB charger cable

My recently bought N800 cannot charge over its USB port (what an utterly stupid design decision!), but the Nokia charger delivers 5V. Since this is the supply voltage of USB, I thought I would buy an adapter. So yesterday I walked into the cell-phone shop and asked. They had one. It cost 79 CHF. (about 50 Euros).

I am afraid I laughed into the face of the poor salesman. He got indignant and told me that he wasn't the one setting the prices. True enough I guess, but I was too busy laughing to reassure him.

Anyway, I decided to build my own USB charger cable. In the photo below you can see the ingredients: (clockwise) A soldering station, callipers, an old Nokia 3.5mm to 2mm converter, shrink-tube and an USB cable in the middle.

I cut of the 2 mm Nokia connector and the male USB connector, and removed the isolation from the cables. Thankfully they are colour-coded: Black for ground and red for 5V. The white and green USB data cables are not needed and get cut off.

Btw, it is important to put on the shrink-tube before soldering anything...

2 minute later: Connections soldered and covered in shrink-tube. I debated whether I should put in a diode, but then couldn't be bothered, and it shouldn't be necessary anyway.

....aaand here we are: Not pretty, but it basically cost nothing, and it does the job.


  1. Neat solution. I got an Old Nokia phone, all my chargers have been lost except for one used in a car.

    Following your instructions, I got an old Nokia USB cable, cut the end of the car charger and connected them together with an old fashioned 2 wire splice.

    Plugged it in and it works like a charm. Thanks a lot :-)

  2. Happy to know I could help someone, and thanks for letting me know!

  3. Hey, I tried this in NOKIA 1650, but keeps saying charger connected, when I put it in my Philips dvd player. Windows 7 PC dont even charge using this circuti.