Datasheet
MCP4017/18/19
DS22147A-page 50 © 2009 Microchip Technology Inc.
8.2 Operational Amplifier
Applications
Figure 8-3 and Figure 8-4 illustrate typical amplifier
circuits that could replace fixed resistors with the
MCP4017/18/19 to achieve digitally-adjustable analog
solutions.
FIGURE 8-3: Trimming Offset and Gain in
a Non-Inverting Amplifier.
FIGURE 8-4: Programmable Filter.
Op Amp
V
IN
V
OUT
–
+
R
1
B
A
V
DD
W
R
3
MCP4018
MCP4017
MCP6291
Op Amp
V
IN
V
OUT
A
B
W
+
–
R
1
B
A
V
DD
W
R
4
f
c
1
2
π
R
Eq
C
⋅⋅
-----------------------------=
R
Eq
R
1
R
AB
R
WB
–+()R
2
R
WB
+()R
w
+
||
=
Thevenin
Equivalent
MCP4018
MCP4018
MCP6021