The AD622 is a low cost, moderately accurate instrumentation amplifier that requires only one external resistor to set any gain between 2 and 1000. For a gain of 1, no external resistor is required. The AD622 is a complete difference or subtracter amplifier system that also provides superior linearity and common-mode rejection by incorporating precision laser-trimmed resistors. The AD622 replaces low cost, discrete, two or three op amp instrumentation amplifier designs and offers good common-mode rejection, superior linearity, temperature stability, reliability, and board area consumption. The low cost of the AD622 eliminates the need to design discrete instrumentation amplifiers to meet stringent cost targets. While providing a lower cost solution, it also provides performance and space improvements.