Q1. Discuss in detail isolation amplifier in detail with diagram?Solution: – Isolation amplifier as the name suggest is a form of differential amplifier that provides electrical isolation and an electrical safety barrier for measuring small signals in the presence of a high common mode voltage.They “re essentially instrumental in practical shielding purposes as they protect data acquisition components from common mode voltages ,which are potential differences between the instrument and signal grounds.
In case where common mode voltage interacts with instruments without isolation amplifier ,usually a noisy representation of the signal under investigation is the final product , this is because of no restrictions on the circulation of ground currents .in case of adequate level of mode voltage for the purpose ,instrument destruction is also a likely income.Isolation amplifier also find implementation in medicine equipment (e.g life support) to ensure isolation of a patient from the leakage current via power supply.
These are also used in shielding the amplifier and instrument as a collective unit without salvaging accuracy of measurement as it allows the front end of the amplifier to float with respect to common mode voltage ,approaching the isolation barrier ‘s breakdown voltage lying in the excess of 1000 volts at times.These amplifiers are also used for amplifying various low level signals in varied multiple channel applications .Measurement errors due to ground loops can also be evaded .Moreover ,amplifiers with internal transformers eliminate external isolated power supply, hence effectively changing the electric regularities to the user and instrument ‘s favour.
They are usually used as analogue interface between Systems with separate grounds.Isolation amplifiers cam also include isolated power supplies for both input output stages ,or external power supplies on each isolated portions for the above usage