I have a circuit with a very-low-power Jennic JN5148 module with microcontroller and 2.4 GHz radio, and some low-power sensors.
I have to measure the supply current of all these components, in an interval of around a second and with a resolution of about 100 uA. These currents may have a maximum value of about 30 mA for the Jennic module, and slightly under 1 mA for the other components.
I should measure these currents simultaneously and at a frequency of about 10 ksample/s, and i need at least 4 channels.
The other requirements are to use as more as possible instruments over building amplifiers and so, and to perturb at least as possible the supply of components. Actually, the requirement is NO COMPONENTS and ONLY INSTRUMENTS.
Does anybody has an idea about the best fitting solution? (i think that i've explained all but tell me if it lacks something)
EDIT: Found this that could be a solution, but can you help me understanding what is the perturbation that it adds to the circuit?