Apparatus and method for eliminating varying pressure fluctuations in a pressure transducer

摘要

A single pressure sensing capsule has a reference pressure ported to the rear side of a silicon sensing die. The front side of the silicon sensing die receives a main pressure at another port. The difference between the main and reference pressure results in the sensor providing an differential pressure output. The reference pressure or main pressure may be derived from a pump pressure which is being monitored. The pump pressure output is subjected to a pump ripple or a sinusoidally varying pressure. In order to compensate for pump ripple, a coiled tube or an adjustable dampening chamber comprising a spiral inlet tube and a volume cavity can be used. The tube length is selected to suppress the pump ripple as applied to the sensor die. In this manner, the pump ripple cannot cause resonance which would result in pressure amplification and which pressure amplification would destroy the sensor.