MCP6051/2/4
1.3
Test Circuits
C
F
6.8 pF
R
G
100 kΩ
V
P
V
IN+
MCP605X
V
IN–
V
M
R
G
100 kΩ
R
F
100 kΩ
C
F
6.8 pF
R
L
10 kΩ
V
OUT
C
L
60 pF
C
B1
100 nF
R
F
100 kΩ
V
DD
V
DD
/2
The circuit used for most DC and AC tests is shown in
This circuit can independently set V
CM
and
V
OUT
; see
Note that V
CM
is not the
circuit’s common mode voltage ((V
P
+ V
M
)/2), and that
V
OST
includes V
OS
plus the effects (on the input offset
error, V
OST
) of temperature, CMRR, PSRR and A
OL
.
EQUATION 1-1:
G
DM
= R
F
⁄
R
G
V
CM
=
(
V
P
+ V
DD
⁄
2
)
⁄
2
C
B2
1 µF
V
OUT
=
(
V
DD
⁄
2
)
+
(
V
P
–
V
M
)
+ V
OST
(
1 + G
DM
)
Where:
G
DM
= Differential Mode Gain
V
CM
= Op Amp’s Common Mode
Input Voltage
V
OST
= Op Amp’s Total Input Offset
Voltage
(V/V)
(V)
(mV)
V
OST
= V
IN–
–
V
IN+
V
L
FIGURE 1-1:
AC and DC Test Circuit for
Most Specifications.
©
2009 Microchip Technology Inc.
DS22182A-page 5
MICROCHIP [ MICROCHIP TECHNOLOGY ]
