MCP6051 Microchip Technology Inc., MCP6051 Datasheet - Page 15

• Manufacturer Part Number: MCP6051
• Description: 30 ?a, High Precision Op Amps
• Manufacturer: Microchip Technology Inc.

4.0
The MCP6051/2/4 family of op amps is manufactured
using Microchip’s state-of-the-art CMOS process and
is specifically designed for low-power, high precision
applications.
4.1
4.1.1
The MCP6051/2/4 op amps are designed to prevent
phase reversal when the input pins exceed the supply
voltages.
exceeding the supply voltage without any phase
reversal.
4.1.2
The ESD protection on the inputs can be depicted as
shown in
protect the input transistors and to minimize input bias
current (I
when they try to go more than one diode drop below
V
V
normal operation and low enough to bypass ESD
events within the specified limits.
FIGURE 4-1:
Structures.
In order to prevent damage and/or improper operation
of these op amps, the circuit they are in must limit the
voltages and currents at the V
Absolute Maximum Ratings at the beginning of
Section 1.0 “Electrical Characteristics”).
shows the recommended approach to protecting these
inputs. The internal ESD diodes prevent the input pins
(V
the resistors R
out of the input pins. Diodes D
input pins (V
V
R
© 2009 Microchip Technology Inc.
SS
DD
DD
2
IN
also limit the current through D
. They also clamp any voltage that go too far above
; their breakdown voltage is high enough to allow
+ and V
. When implemented as shown, resistors R
V
V
V
IN
DD
SS
+
APPLICATION INFORMATION
Rail-to-Rail Input
B
). The input ESD diodes clamp the inputs
Figure
Figure 2-34
Bond
Bond
Bond
PHASE REVERSAL
INPUT VOLTAGE AND CURRENT
LIMITS
Pad
Pad
Pad
IN
IN
-) from going too far below ground, and
1
+ and V
and R
4-1. This structure was chosen to
2
Simplified Analog Input ESD
limit the possible current drawn
IN
Stage
Input
shows
-) from going too far above
IN+
1
1
the
and D
and V
and D
Bond
Pad
input
2
IN-
2
prevent the
.
Figure 4-2
V
pins (see
IN
voltage
–
1
and
FIGURE 4-2:
Inputs.
It is also possible to connect the diodes to the left of the
resistors R
the diodes D
mechanism. The resistors then serve as in-rush current
limiters; the DC currents into the input pins (V
V
current can flow out of the inputs when the common
mode voltage (V
Figure
4.1.3
The input stage of the MCP6051/2/4 op amps uses two
differential input stages in parallel. One operates at a
low common mode input voltage (V
operates at a high V
operates with a V
300 mV below V
voltage is measured at V
V
The transition between the input stages occurs when
V
Figure
gain linearity, with non-inverting gains, avoid this region
of operation.
4.2
The output voltage range of the MCP6051/2/4 op amps
is
(maximum) when R
and V
more information.
IN
DD
CM
-) should be very small. A significant amount of
V
+ 0.3V to ensure proper operation.
is near V
SS
V
V
DD
2-36).
2-6). For the best distortion performance and
1
2
Rail-to-Rail Output
+ 15 mV
R
R
= 6.0V. Refer to
1
1
2
NORMAL OPERATION
and R
1
>
>
and D
R
R
V
V
1
2
DD
D
SS
SS
SS
1
CM
2
CM
. (See
– (minimum expected V
– (minimum expected V
– 1.1V (See
. In this case, the currents through
2
MCP6051/2/4
L
CM
(minimum)
) is below ground (V
need to be limited by some other
D
= 10 kΩ is connected to V
Protecting the Analog
up to 300 mV above V
. With this topology, the device
2
Figure
Figures 2-27
2 mA
2 mA
CM
MCP605X
2-13) .The input offset
Figures
V
and
= V
R
CM
DD
3
DS22182A-page 15
), while the other
SS
and
V
2-4,
– 0.3V and
DD
1
2
)
)
SS
2-5
– 15 mV
2-28
IN
). (See
DD
+ and
DD
and
and
for
/2