How does current-sense amplifier work?

How does current-sense amplifier work?

A current sense amplifier is a special purpose integrated circuit differential amplifier that is designed to sense the voltage developed across a current shunt and output a voltage proportional to the measured current. These devices are designed to handle common mode voltages in excess of their own supply voltage.

What is the use of sensing amplifier circuit?

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 differential current sense amplifier work?

Current-sense amplifiers such as the AD8210 amplify the small differential input voltage in the following manner. The input terminals are connected to the differential amplifier, A1, by R1 and R2. A1 nulls the voltage appearing across its own input terminals by adjusting the current through R1 and R2 with transistors Q1 and Q2.

What kind of amplifier is used for current sensing?

This article introduces the four differential amplifiers that typically are used in direct current sensing solutions: operational amplifiers (op amps), difference amplifiers (DA), instrumentation amplifiers (IA), and current shunt monitors (CSM). The use of an op amp for current sensing is limited by input common-mode voltage.

Can a difference amplifier be used for low side sensing?

Difference amplifiers, however, can be used for high-side current sensing in the presence of high common-mode voltages at the expense of drawing current from the system bus supply. They can also be used for low-side sensing and negate the effects of parasitic resistances to ground.

How are the input terminals connected to the differential amplifier?

The input terminals are connected to the differential amplifier, A1, by R1 and R2. A1 nulls the voltage appearing across its own input terminals by adjusting the current through R1 and R2 with transistors Q1 and Q2. When the input signal to the AD8210 is 0 V, the currents in R1 and R2 are equal.