Circuit to measure current consumption of uC

I'd try a 10 Ohm Shunt in the GND path and measure with a 24bit ADC.

1nA :) sounds like fun

Bandwith? Uncertancy?

All will be for naught if you don't monitor the voltage to keep it 
stable....

and take some expensive low leakage components ...

Bop Pease had some stories about low current measurements on components 
and Jim Williams too (on crystals, however always worth the time)

One idea: Take a big (low leakage) cap for the supply of your DUT and 
charge it with a small cap of a (slightly) higher constant voltage, 
controlled by a comparator. The number of charge pulses per time is your 
current.

Tricky is the switch :)

Or take a look at current output DAC ..

http://www.alternatezone.com/electronics/ucurrent/

HTH

> http://www.alternatezone.com/electronics/ucurrent/

I have it (DIY), it is GREAT!

@oork: this did not work unfortunately
@henrik: I want to have as much accurate results as possible. What do 
you mean with Bandwidth?
@g457: yes but I need the circuit of it. I need to build my own 
circuit...

Appreciate it!!
Thank you so much, it seems to be what I need... I'm gonna try to 
simulate the circuit and hopefully it works.
thx again