Phone charger for Power Supply?

[ngp99]

I am on my third Sony T6xx phone and so have a couple of spare chargers. Output is 5.12v 450mA. Would one of these be OK as an external supply? I realise that the voltage is only just over the regulated 5v, so I hope there would be nothing subtle going on. I am only reading sensors, no motors.

My EtherTen board got distressingly hot when I leaned 12v against it.

Thank you

[Flymo]

Greetings!

You should be fine - there is always a tolerance on power supply voltages, and in the case of USB, 5 volts means "between 4.75 and 5.25 volts". There's more on Wikipedia here:-
http://en.wikipedia.org/wiki/Universal_Serial_Bus#Power

Worth checking the total current your EtherTen project is drawing. One of my projects was taking 720mA total, due to a thirsty prototyping shield etc. Needed 2x USB feeds from the laptop to make it work right.

If yours works well on a single USB feed (500mA) it should *probably" be good on 450 mA, but it would be good to be certain of that.

hth!

[ngp99]

Thanks for your comment. I have gone ahead and put a concentric on the Sony charger. My concern was putting this voltage through the on-board regulator rather than supplying through the USB port.

I take your point about ensuring adequate power. When I connected a temperature probe to my proto shield, the blue light on the EtherTen went out and the PC went ding!

[jebz]

I have gone ahead and put a concentric on the Sony charger.

You need 7v on the coaxial dc power connection or it will not work reliably.
http://www.freetronics.com/pages/ethert ... EmpySKHlJk

[rebboc]

I have been able to power the Etherten successfully with a 9V plugpack ex a dead wireless router and with a USB charger ex a dead mobile phone. The USB charger I just plugged into the USB connection on the Etherten.

[ngp99]

It appears that the charger is not up to the job when I use the ethernet facility. I believe it is OK for anything else.

[JHern]

I went to the local electronics surplus store today and bought this supply and cord. Next I went to radio shack and bought banana jacks, a switch and 2 - 50 ohm 10 watt resistors. Total expendature $28.36. Very cheap for a 12 volt 10 amp switching supply with 5 volts 25 amps as a bonus.