On 21 Jan 2017 22:46:27 GMT, Bob Eager wrote:

On Sat, 21 Jan 2017 19:29:42 +0000, Scott wrote:

On Sat, 21 Jan 2017 18:33:42 +0000, alan_m
wrote:

On 21/01/2017 18:16, Scott wrote:

As a matter of interest, why to the 12 Volt ones seem to be more
problematic than the mains ones?


Current to be supplied?

10W from 220V, current to be supplied 0.045 Amps

10W from 12V, current to be supplied 0.833 Amps

The low supply voltage power supply is switching high currents.
The mains supply is switching low currents.

That makes sense. I had not thought of that.

I take it this 'switching' is what they used to call 'rectifying' when I
was at school?

No.

https://en.wikipedia.org/wiki/Switch...e_power_supply

Thanks. I don't follow it all but I am getting the idea. I will
Google linear regulators later.