An ideal operational amplifier amplifies weak signals as they are, but there are many factors that can degrade accuracy. Input bias current is the current flowing through the input terminals of the op amp and affects the output of the sensor itself. Input offset voltage causes a clog-like shift in the overall output of the op amp. Input equivalent noise voltage is a random voltage error generated by the internal elements. Because offset voltage and noise also increase with amplification at higher magnification, low-offset, low-noise op amps are required for high-precision sensor systems.