Can a resistor change value?
Instead of ordering and wanting for a resistor with a value you need you can change the resistance of a resistor by using another resistor or many. By installing resistors in a parallel or series circuit you can change the value in Ohms. You will need a few resistors.
What is the essence of a resistor?
Resistor Definition and Symbol A resistor is a passive electrical component with the primary function to limit the flow of electric current.
How does a current sense resistor circuit work?
The above current sense resistor circuit shows how a shunt resistor is placed in a current carrying path and how the voltage drop across the resistor can be calculated by using a Current Sense Amplifier. You can know more about how current sense amplifiers work for following the linked article.
Why do we need a current sense amplifier?
These amplifiers are designed for the special purpose, so that the amplifier could amplify a very small amount of sensed voltage across the shunt resistor, typically in 10 to 100 mV range. Current Sense amplifiers are made for DC precision (For example, low input offset voltage) and high common-mode rejection ratio (CMRR).
How is the value of a shunt resistor determined?
Because the value will determine how much voltage will drop during the flow of current. The value can be determined from the current sense amplifier perspective. Depending on the maximum current flow and the maximum input voltage of the current sense amplifier, the value of the shunt resistor can be chosen.
What should the voltage of a sensing resistor be?
In practice, it’s generally desirable to keep the maximum voltage across the sensing resistor to 100 mV or below, so that the corresponding resistor values are in the tens-of-milliohms range and even lower. Sense resistors are widely available in these small values; even 1-mΩ and lower resistors are standard catalog offerings (Fig. 5).