The goal is to use 4 units of 50kg load cells in Wheatstone bridge to act as a load detector. It should output a logic 0 or 1 if the load is greater than a threshold value. A MCU will read the states of 100 load detectors through a series of PISO shift register. Potentiometers will be used to adjust threshold level and they have to be placed near the MCU which is 5-10 meters away from the load detectors.
I have trouble determining a circuit to read the differential voltage signals from the bridge. A signal amplifier IC and a comparator IC might be sufficient. But is there other approach?
The default load is around 2kg. The threshold is around 5kg-20kg.
Hi,
Google arduino load cell
or
Google HX711
Tom... 
TomGeorge:
Google arduino load cell
or
Google HX711
I tried to use HX711 module but it requires a clock signal and outputs digital signals. I don't need a precise weight reading but a logic 0 or 1 signal when the weight is over a threshold value.
Hi,
Well you are going to have to measure the outputs to check them against a threshold value.
Can you tell us the application of your project please that uses 100 mass sensors?
Have you got a load-cell setup so you can measure the output of the bridge so you know how sensitive the comparator circuit will have to be?
Google wheatstone bridge differential amplifier
Thanks .. Tom... 