MCP6V06 Microchip Technology Inc., MCP6V06 Datasheet - Page 27

• Manufacturer Part Number: MCP6V06
• Description: 300 ?a, Auto-zeroed Op Amps
• Manufacturer: Microchip Technology Inc.

4.3.9.3
Figure 4-12
fier circuit. Usually, we choose R
The guard traces (with ground vias at the ends) help
minimize the thermal gradients. The resistor layout
cancels the resistor thermal voltages, assuming the
temperature gradient is constant near the resistors:
EQUATION 4-3:
FIGURE 4-12:
for Single Difference Amplifier.
© 2008 Microchip Technology Inc.
Where:
Thermal voltages are approximately equal
Note:
V
G
V
M
P
DM
V
V
M
P
Changing the orientation of the resistors
will usually cause a significant decrease in
the cancellation of the thermal voltages.
shows the recommended difference ampli-
V
V
=
MCP6V06
Difference Amplifier Layout for
Thermo-junctions
OUT
OUT
R4
R2
R1
R3
R
V
R
≈ V
≈ V
R
3
OS
1
2
/R
U
REF
REF
is neglected
1
1
PCB Layout and Schematic
= R
+ (V
+ (V
4
R
R
/R
P
P
4
3
U1
2
– V
– V
, difference gain
1
= R
M
M
V
)G
)G
2
REF
DM
DM
V
and R
OUT
V
V
3
OUT
REF
= R
4
.
4.3.9.4
The dual op amp amplifiers shown in
Figure 4-17
greater than 1, and a common mode gain of 1 .They
can use the layout shown in
ting resistors (R
bined so that the thermal voltages can be canceled.
The guard traces (with ground vias at the ends) help
minimize the thermal gradients. The resistor layout
cancels the resistor thermal voltages, assuming the
temperature gradient is constant near the resistors:
EQUATION 4-4:
FIGURE 4-13:
for Dual Non-inverting Amplifier.
Where:
Thermal voltages are approximately equal
Note:
G
G
R3
R2
R1
DM
CM
V
V
IA
IB
=
=
Changing the orientation of the resistors
will usually cause a significant decrease in
the cancellation of the thermal voltages.
(V
(V
produce a non-inverting difference gain
Dual Non-inverting Amplifier Layout
for Thermo-junctions
½ MCP6V07
½ MCP6V07
OA
OA
1 + R
1, common mode gain
V
2
) between the two sides are not com-
OS
– V
+ V
V
MCP6V06/7/8
is neglected
3
OB
OA
OB
R
R
R
R
/R
V
PCB Layout and Schematic
1
1
2
2
IA
U1
) ≈ (V
)/2 ≈ (V
2
U
U
, differential mode gain
1
1
V
Figure
IA
IB
IA
– V
R
R
V
3
3
+ V
OB
IB
4-13. The gain set-
DS22093B-page 27
)G
IB
Figure 4-16
)/2
DM
V
V
OA
OB
R3
R2
R1
and