to electronic systems have historically been based upon classic instrumentation amplifier designs. Instrumentation amplifiers have been widely used because they are wellunderstood standard building blocks that also work reasonably well. For the specific job of interfacing Semiconductor Pressure Sensors to today’s mostly digitalsystems, other circuits can do a better job. This application note presents an evolution of amplifier design that begins with a classic instrumentation amplifier and ends with a simpler circuit that is better suited to sensor interface.