Some techniques for precision monolithic circuits applied to an instrumentation amplifier

Precision monolithic circuit functions can be fabricated if proper circuit and processing techniques are incorporated. Compatible thin-film-on- silicon technology is coupled with annealing of individual resistors with a focused laser beam to provide a means for fabricating monolithic circuits in the 0.1 to 1.0 percent accuracy range. It is shown that special circuit techniques, which accommodate uniquenesses of available monolithic devices, must be used to obtain optimum circuit performance. The design of an instrumentation amplifier that incorporates emitter feedback and direct compensation of dc errors is described, together with test results that validate the techniques discussed.