How do you choose an appropriate shunt resistor?
Several parameters are important to specify a shunt resistor. Shunt resistors have a maximum current rating. The resistance value is given by the voltage drop at the maximum current rating. For example, a shunt resistor rated with 100 A and 50 mV has a resistance of 50 / 100 = 0.5 mΩ.
What are current sense resistors?
A current sensing resistor is designed for low resistance so as to minimize power consumption. As a result, the calibrated resistance senses the current flowing through it in the form of a voltage drop which is detected and monitored by the control circuitry.
What is the function of sense amp in DRAM structure?
A sense amplifier is part of the read circuitry that is used when data is read from the memory; its role is to sense the low power signals from a bitline that represents a data bit (1 or 0) stored in a memory cell, and amplify the small voltage swing to recognizable logic levels so the data can be interpreted properly …
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’s the maximum rating for a sense amplifier?
Since the maximum current rating is 1A, and no specified load is described, a current sense amplifier needs to be selected that works with 12V supply and could sense more than the 1A of the current rating. As discussed, one needs to select something for the low-level side or high-level side.