Rockbox mail archive
Subject: Re: Shamingly obvious question about NiMH vs NiCad chargers
From: gerald clark (gerald_clark_at_mindspring.com)
The current rating on a DC power supply is the maximum current that can
be supplied without exceeding allowable ripple in the output.
It is not a current limiting specification, but a current supplying
You may use less than the rated current, but you can not use more
without risking damage to the equipment being powered.
George Michaelson wrote:
> God, how embarrassing not to know these things.
> If one owns an older tandy (blush) NiCad charger, is this 'safe' to use to
> re-charge NiMH or are they radically different and require a different charger
> and current?
> Also, I spoke to a source of AC/DC plugpacks yesterday and he was pretty
> adamant that the current limiting requirement to 600ma from the 9v pack or
> 1.2a from the 12v pack was meaningless, it was the device which determined how
> much current was drawn. I didn't buy this, but also I don't *understand* this
> I'm not an electrical engineer. I don't even play one in Soap Operas. I don't
> intend risking my device either, so I'm sticking to my US charger in a
> 240v->110v stepdown unit until I can get a regulated 9v/600ma DC block. I
> tried one rated to 300ma, it didn't charge, but it does trigger the poweron
> behaviour of the volts-in, I guess thats a mechanical switch right?
Gerald L. Clark
Aero TerraTrike #1
Member: Sky Soaring
Page was last modified "Jan 10 2012" The Rockbox Crew