Question

The amplifier configuration must contain _____________ to achieve the low frequency response for medical applications?

(a) higher resistance

(b) lower resistance

(c) lower capacitance

(d) higher capacitance

This question was posed to me during an interview.

This intriguing question comes from Telemedicine System topic in chapter Telemedicine Technology of Biomedical Instrumentation

Answer 1

Right option is (d) higher capacitance

Explanation: To achieve the low frequency response required for medical applications, the amplifier must have large values of coupling capacitance.  The response should be down to less than one hertz which is a very frequent requirement. In all RC-coupled amplifiers, low frequency response is limited by the reluctance of the coupling capacitors.