What is the primary purpose of an isolation amplifier in a signal chain?

What is the primary purpose of an isolation amplifier in a signal chain?

• A. To increase signal amplitude while sharing ground.
• B. To provide galvanic isolation and preserve signal integrity.
• C. To convert analog to digital for transmission.
• D. To filter high-frequency noise at the source.

Answer: (B)

Isolation amplifiers create a barrier between input and output so there’s no direct electrical connection. This galvanic isolation prevents ground loops and differences in ground potential from corrupting the signal, protecting both equipment and the measurement itself. At the same time, the device transfers the signal with good fidelity, often through buffering and a defined gain, so the output accurately reflects what’s on the input without the disturbances tied to the source’s ground. This is especially important in systems with multiple grounds or safety concerns, where a fault or noise on one side shouldn’t propagate to the other. They aren’t mainly used to boost amplitude, convert analog to digital, or filter high-frequency noise—that’s the job of other circuit stages. The isolation barrier also helps keep the signal clean from common-mode disturbances, improving overall measurement integrity across the chain.

Isolation amplifiers create a barrier between input and output so there’s no direct electrical connection. This galvanic isolation prevents ground loops and differences in ground potential from corrupting the signal, protecting both equipment and the measurement itself. At the same time, the device transfers the signal with good fidelity, often through buffering and a defined gain, so the output accurately reflects what’s on the input without the disturbances tied to the source’s ground. This is especially important in systems with multiple grounds or safety concerns, where a fault or noise on one side shouldn’t propagate to the other. They aren’t mainly used to boost amplitude, convert analog to digital, or filter high-frequency noise—that’s the job of other circuit stages. The isolation barrier also helps keep the signal clean from common-mode disturbances, improving overall measurement integrity across the chain.