Do you need a sensor that provides you with perfectly precise and exact measurements for AC signals and DC signals? Also, regarding the overall power consumption in systems, this sensor is capable of measuring and metering them. The range of measurements is does can reach up to 5A (DC or AC).
In addition to that, in order to be able to allow even more sensitive measurements, an opamp gain stage has been carefully added. Now, you can freely measure very small currents and be satisfied.
The output of ACS712 Low Current Sensor is basically an analog voltage which varies in a linear manner compared with the sensed current.
Follow the following instruction to calibrate and check:
• First set the output offset to the desired level (with zero current on the sense lines, read output with a DVM)
• Then with a known current input (a 100mA limited supply works well for this), set the output deflection with the gain pot.
• Sensitivity is then calculated as (Vref - Vdeflect)/(current input).
A bandwidth of 34Hz has been chosen for this product, since this number allows reducing the noises in case high gains were used. On the other hand, 80KHz bandwidth can still be recovered simply through removing C1.