“The pressure sensor amplifier built using LM358 op-amp and MPXM2051GS pressure sensor from NXP semiconductor. The circuit provides 4V output for full scale pressure input 0-7.5PSI. One op-amp is used as amplifier and 2nd op-amp is used as comparator to provide an output at set value that can be used as over pressure switch to control a pump or solenoid. This is a low cost general-purpose circuit for those applications where +/-3% performance is acceptable. Multi turn potentiometers are provided for Offset, span adjust & over/under Pressure set point to control output devices like solid state relay, Pump, and solenoid.”