VTI Instruments EX1629 - Full-Bridge Poisson; Full-Bridge Bending Poisson

VTI Instruments Corp.
46 EX1629 Basic Operation
The full-bridge strain conversion is calculated according to:
sense-sensediff
VVV
excitation
unstraineddiff
V
VV
V
r
GF
V
r
Setting this conversion automatically configures the input path for full-bridge mode, in which the
completion resistor is shorted and the back-half resistors are disconnected. This configuration is
illustrated in Figure 2-5.
Full-Bridge Poisson
This conversion applies to the following bridge configuration:
+
+
–
+
–
+
–
–
V
OUT
V
EXC
FIGURE 3-6: FULL-BRIDGE POISSON CONFIGURATION
The full-bridge strain conversion is calculated according to:
sense-sensediff
VVV
excitation
unstraineddiff
V
VV
V
r
11
2
r
r
VGF
V
Setting this conversion automatically configures the input path for full-bridge mode, in which the
completion resistor is shorted and the back-half resistors are disconnected. This configuration is
illustrated in Figure 2-5.
Full-Bridge Bending Poisson
This conversion applies to the following bridge configuration:
+
+
–
+
–
+
–
–
V
OUT
V
EXC
FIGURE 3-7: FULL-BRIDGE BENDING POISSON CONFIGURATION