2mA - 30mA Current sensor using Instrumentation or Current sense amplifier

Hi guys,

I am going to build a simple circuit for current measurement. I am facing a problem in measuring a current range from 2mA- 30mA for my project. FYI, my system operates at 3.5- 5V. Any recommendation for the selection of components(both amplifier & shunt resistor)?

Please see the file attached.

Regards,
Jaysee

clip_image001_20080309140125.jpg

Do a Google search for "high side current sense amplifier", then read the datasheets.

I have decided to use:

as my current sense amplifier. But for the current sensing resistance, I am not too sure what is the value to be used in my application ( Measuring 2mA -30mA )..

Can anyone please share their knowledge? Thanks.

Following link is the available range of current sensing resistance:

https://www.digikey.com/Web%20Export/Supplier%20Content/tt-electronics-welwyn-985/pdf/welwyn-an-current-sense-resistors.pdf?redirected=1

Thank you very much!

Decide what you want the output voltage to be at full scale.
Divide that by the gain to give the required voltage drop across the resistor (there are 3 versions of the device with different gains).
Calculate the resistor value that gives the required voltage drop at 30mA.