Currentmeter project I need help!!!

[TjayS]

I am designing a circuit that can measure the current in a Microkontroller. the values should be between 0.1uA and 100 mA. As you can see it's a very large area. I constructed two designs where one of them is pretty accurate in the area between 60uA and 100mA. but under 60uA I get wrong measurment.
I'm using MOS switchs to switch between the resistors. but I can't find something that helps.

I'm out of Ideas!!!! Is there any one hear who can help?? or any Idea that can help to measure 0.1uA.???

New thing , the circuit 2 work pretty accurate down to 10uA.
than the difference becomes bigger and bigger for smaller measurments

 

[Nigel Goodwin]

Re: Currentmeter project

I am designing a circuit that can measure the current in a Microkontroller. the values should be between 0.1uA and 100 mA. As you can see it's a very large area. I constructed to designs where one of them is pretty accurate in the area between 1,5mA and 100mA. but under 1mA I get wrong measurment.
I'm using MOS switchs to switch between the resistors. but I can't find something that helps.

I'm out of Ideas!!!! Is there any one hear who can help?? or any Idea that can help to measure 0.1uA.???

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Try posting the circuit you are currently using, but MOS switches don't sound a good idea for switching between ranges!.