Datasheet

SBOA102A
January 2005
Sensor-Emulator-EVM
System Reference Guide
11
Emulating a Temperature Sensor
with a Series Bridge Resistor
(R
t+
connected to
the top of
the bridge)
The sensor emulator circuit can also emulate the case where the temperature sense resistor is connected to the top of the bridge. This is done
using an instrumentation amplifier to translate the voltage signal to be referenced to Vexcrather then ground. This mode of operation is
selected by a jumper (JUMP1). This circuit also feeds the temperature signal back to the bridge emulator to adjust the excitation across the
bridge, as in the real world case. The details of how this feedback works are described in Figure 2.15.
Figure 2.9 Figure 2.10 Figure 2.11
V
T
V
exc
R
T
⋅
R
T
R
Bridge
+