Autozeroed amplifier with halved noise needs few components

摘要

The Analog Devices AD8553 autozeroed instrumentation amplifier has a unique architecture in that its two gain-setting resistors have no common junction (Reference 1). The first stage of the IC is a precise voltage-to-current converter, in which the first gain-setting resistor, R_1, sets the magnitude of the transconductance. The end stage of the IC is a precise current-to-voltage converter, in which the value of its feedback resistor, R_2, co-determines the overall voltage gain as G=2(R_2/R_1).