Datasheet

MCP40D17/18/19
DS22152B-page 52 © 2009 Microchip Technology Inc.
8.4 Wheatstone Bridge Trimming
Another common configuration to “excite” a sensor
(such as a strain gauge, pressure sensor or thermistor)
is the wheatstone bridge configuration. The
wheatstone bridge provides a differential output
instead of a single-ended output. Figure 8-7 illustrates
a wheatstone bridge utilizing one to three digital
potentiometers. The digital potentiometers in this
example are used to trim the offset and gain of the
wheatstone bridge.
FIGURE 8-7: Wheatstone Bridge
Trimming.
V
DD
V
OUT
5kΩ
50 kΩ 50 kΩ
MCP40D17
MCP40D17
MCP40D17