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Current sensing wide range low to mid current

Hi

We need to measure a device that working under different current consumption

0.1uA to tens of mA (60-100mA) 

Do you have any recommendation for components that can help to measred such wide current range

  • Hello Snir,

    Thank you for considering to use Texas Instruments for your current sensing application. Our current shunt devices typically have a fixed gain, so it is unlikely you will be able to cover such a wide range with those alone. Our adjustable gain devices similarly would have problems accommodating such a range as those are typically controlled by a resistor value. However, if you absolutely need to measure this range and happen to have already a microcontroller nearby on board, you could potentially have the microcontroller toggle a FET switch that would either change the shunt resistor used or the gain setting resistor when certain output thresholds are exceeded for a given state. What kind of resolution are you trying to achieve in your measurements and what is the range of your common mode voltage?
  • In reply to Patrick Simmons:

    Hello Snir,

    In addition to Patrick's comment on the range of current measurement being difficult with a single shunt/amplifier, the low-end of the current you want to measure (0.1uA)  is less than any of our current sense amplifiers can measure due to the bias current on the inputs pins of the device.  For measuring this current level, you need to look at instrumentation amplifiers that have extremely low bias currents.

    Regards, Dan