> I need to turn on and off a load that takes very little 
> power (a few ma at 3V). I want all the power I supply to 
> the circuit goes mostly to the load itself but not the 
> switching device. I couldn't use a relay since the relay 
> coil consumes too much power. I don't even want to use a 
> transistor as a switch, because when it is saturated, 
> there is a certain volt-drop across it, hence some power 
> is lost in the transistor. Is there any component (or 
> methods) that could be used as a switch and at the same 
> time the power loss in the switch itself is very low?


More information would help BUT
A MOSFET will very probably do what you want.
FDN337 or FDN338 are a good start depending on whether you 
want a low side or a high side switch.
See eg  www.digikey.com

Power consumption off or on is about zero.
Voltage drop when on is about zero.


        Russell McMahon 

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