Datasheet

MCP6051/2/4
DS22182B-page 18 © 2010 Microchip Technology Inc.
4.7.2 INSTRUMENTATION AMPLIFIER
The MCP6051/2/4 op amps are well suited for
conditioning sensor signals in battery-powered
applications. Figure 4-9 shows a two op amp
instrumentation amplifier, using the MCP6052, that
works well for applications requiring rejection of
common mode noise at higher gains. The reference
voltage (V
REF
) is supplied by a low impedance source.
In single supply applications, V
REF
is typically V
DD
/2.
FIGURE 4-9: Two Op Amp
Instrumentation Amplifier.
To obtain the best CMRR possible, and not limit the
performance by the resistor tolerances, set a high gain
with the RG resistor.
4.7.3 PRECISION COMPARATOR
Use high gain before a comparator to improve the
latter’s input offset performance. Figure 4-10 shows a
gain of 11 V/V placed before a comparator. The
reference voltage V
REF
can be any value between the
supply rails.
FIGURE 4-10: Precision, Non-inverting
Comparator.
V
OUT
V
1
V
2
–()1
R
1
R
2
----- -
2R
1
R
G
---------++
⎝⎠
⎛⎞
V
REF
+=
V
REF
R
1
R
2
R
2
R
1
V
OUT
R
G
V
2
V
1
½½
MCP6052
MCP6052
V
IN
1MΩ
V
OUT
100 kΩ
MCP6541
V
REF
MCP6051