ZHCSH46A December 2017 – June 2018 AMC1311
Isolated amplifiers are widely used in frequency inverters that are critical parts of industrial motor drives, photovoltaic inverters, uninterruptible power supplies, and other industrial applications. The input structure of the AMC1311 is tailored for isolated voltage sensing using resistive dividers to reduce the high common-mode voltage.
Figure 49 depicts a typical use of the AMC1311 for dc bus voltage sensing in a frequency inverter application. Phase current measurement is accomplished through the shunt resistors, RSHUNT (in this case, two-pin shunts) and the AMC1301 isolated amplifiers that are optimized for isolated current sensing. The high-impedance input and the high common-mode transient immunity of the AMC1311 ensure reliable and accurate operation even in high-noise environments, such as the power stage of frequency inverters as used in motor drives.