Brands
Vishay Measurements Group
Interactive Guide
Tech Notes
TN-510
|
|
Design Considerations For
Diaphragm Pressure Transducers
|
|
LINEARITY
The preceding equations for diaphragm strain and output indicate that the output is proportional to the applied pressure. This precise linearity applies, however, only for vanishingly small deflections. In the case of finite deflections, the diaphragm pressure transducer is inherently nonlinear, and becomes more so, as deflection increases. As a general rule, the deflection of the diaphragm at the center must be no greater than the diaphragm thickness; and, for linearity in the order of 0.3%, should be limited to one quarter the diaphragm thickness. Following is the formula for diaphragm deflection, based upon small-deflection theory: 
(5)
where: 
= Center deflection, in (
mm
)
Page 7 of 12 |