Digital Weighing Scales are basically a replacement of the traditional Analog Scale. Just like the Analog Weighing Scales, the Digital Weighing Scales are also used to check the body weight. These days, they have gained a lot more popular because it is easy to read the weight on the Digital Weighing Scale and it offers a reading upto 1 decimal place.
In the Digital Weighing Scale, the spring mechanism is replaced with the digital circuit which is pre-calibrated to check the weight. The circuit is then connected to a small display which enables the user to check the reading. If you are wondering that how does a Digital Weighing Scale works then here is the answer to your question.
-} The basic components of the digital weighing scale include a load cell which is nothing but a four strain gauges arranged in a wheat stone bridge format.
-} If you do not know about the strain gauge, then you must know that these are the small devices which have a property of changing their resistance on the application of an external strain.
-} The output of this load cell is then amplified with help of an amplifier and the output is then filtered with a digital filter. This output is then fed to an ADC and this helps the user in reading the weight on the digital display as the ADC converts this analog value to a digital one before feeding it further.
-} All the digital weighing scales need a battery to run and most commonly used batteries in these types of scale are AAA batteries. The batteries provide the power to the circuit which enables the load cell to measure the change in the resistance.
This is how a digital weighing machine works and the components in the weighing scale are really small as compared to the one in the Analog Scale.