Optimizing nonlinearity of piezoresistive pressure sensors by an asymmetric Wheatstone bridge

Since nonlinearity is critical to silicon piezoresistive pressure sensors, this paper combined theoretical analysis and simulation to study the effect of changing the longitudinal resistance (R L ) and transverse resistance (R T ) on the nonlinearity of pressure sensors. When initial longitudinal resistance (R L0 ) is larger than initial transverse resistance (R T0 ) and the difference is within a certain range, the nonlinearity of the pressure sensor can be effectively reduced. And based on this discovery, a method of an asymmetric Wheatstone bridge for optimizing nonlinearity of piezoresistive pressure sensors was proposed, which could reduce the nonlinearity from 10 –3 to 10 –6 order of magnitudes in the simulation.