flexing of the membrane so that the factor u03c4 u2032 u03c4 does not reduce the signal amplitude significantly this can always be arranged by having the cavity volume sufficiently large to be useful for well testing applications the time constant needs to be on the order of one second one embodiment of a sensor that gives such a time constant u03c4 u2245 1 sec has the following dimensions and parameters u03bc 10 u2212 3 pa s viscosity of water one can easily use a fluid with higher viscosity d 3 u03bcm 3 10 u2212 6 m possible with micro fabrication etching techniques for the construction of mems devices l 20 mm 2 10 u2212 2 m the capillary can meander to have a significant length in a small area v 10 u2212 19 m 3 for example 1 mm by 1 mm by 100 microns dimensions currently found in mems pressure sensors the volume of the capillary is on the order of 10 u2212 13 much smaller than v so that neglecting compressibility in the capillary is justified c 10 u2212 9 pa u2212 1 an intermediate value in the relevant range and neglect k thus it is possible to design a sensor with the desired response that can be fabricated using conventional mems techniques the greatest challenge is to obtain the small value of d used in the example above but this can be relaxed increasing v l and c e g with a gas bubble in a different embodiment of the invention an array of sensors as described above is used each with a different time constant such an array can act as a replacement for an accurate high end absolute pressure sensor.