Journal of micromechanics and microengineering vol:11 issue:4 pages:390-396
This article describes the experimental verification of the hydraulic time constant related to the reference channel of a micromachined differential pressure sensor. A pressure shock wave is employed to apply a fast step impulse of large amplitude to the device under test. The impulse response of the device is captured. The hydraulic time constant of the system consisting of a channel of cross section 100 x 1 mum(2) and length 1.6 mm and a cavity of 700 x 700 x 1 mum(3) is found to be about 1.2 ms. The experimental results are compared to predictions obtained by a number of analytical models and finite element simulations.