MCP6491/2/4
7.5 MHz, Low-Input Bias Current Op Amps
Features
• Low-Input Bias Current
- 150 pA (typical, T
A
= +125°C)
• Low Quiescent Current
- 530 µA/amplifier (typical)
• Low-Input Offset Voltage
- ±1.5 mV (maximum)
• Supply Voltage Range: 2.4V to 5.5V
• Rail-to-Rail Input/Output
• Gain Bandwidth Product: 7.5 MHz (typical)
• Slew Rate: 6 V/µs (typical)
• Unity Gain Stable
• No Phase Reversal
• Small Packages
- Singles in SC70-5, SOT-23-5
• Extended Temperature Range
- -40°C to +125°C
Description
The Microchip MCP6491/2/4 family of operational
amplifiers (op amps) has low-input bias current
(150 pA, typical at 125°C) and rail-to-rail input and
output operation. This family is unity gain stable and
has a gain bandwidth product of 7.5 MHz (typical).
These devices operate with a single-supply voltage as
low as 2.4V, while only drawing 530 µA/amplifier
(typical) of quiescent current. These features make the
family of op amps well suited for photodiode amplifier,
pH electrode amplifier, low leakage amplifier, and
battery-powered signal conditioning applications, etc.
The MCP6491/2/4 family is offered in single
(MCP6491), dual (MCP6492), quad (MCP6494)
packages. All devices are designed using an advanced
CMOS process and fully specified in extended
temperature range from -40°C to +125°C.
Related Parts
• MCP6471/2/4: 2 MHz, Low-Input Bias Current Op
Amps
• MCP6481/2/4: 4 MHz, Low-Input Bias Current Op
Amps
Applications
•
•
•
•
•
•
Photodiode Amplifier
pH Electrode Amplifier
Low Leakage Amplifier
Piezoelectric Transducer Amplifier
Active Analog Filter
Battery-Powered Signal Conditioning
Design Aids
•
•
•
•
•
SPICE Macro Models
FilterLab
®
Software
MAPS (Microchip Advanced Part Selector)
Analog Demonstration and Evaluation Boards
Application Notes
Package Types
MCP6491
SC70, SOT-23
V
OUT
1
V
SS
2
V
IN
+
3
5
V
DD
4
V
IN
–
MCP6492
SOIC, MSOP
V
OUTA
1
V
INA
–
2
V
INA
+
3
V
SS
4
8
V
DD
7
V
OUTB
6
V
INB
–
5
V
INB
+
MCP6492
2x3 TDFN*
V
OUTA
1
V
INA
–
2
V
INA
+
3
V
SS
4
EP
9
8
V
DD
7
V
OUTB
6
V
INB
–
5
V
INB
+
MCP6494
SOIC, TSSOP
V
OUTA
1
V
INA
–
2
V
INA
+
3
V
DD
4
V
INB
+
5
V
INB
–
6
V
OUTB
7
14
V
OUTD
13
V
IND
–
12
V
IND
+
11
V
SS
10
V
INC
+
9
V
INC
–
8
V
OUTC
* Includes Exposed Thermal Pad (EP); see
Table 3-1.
2012-2013 Microchip Technology Inc.
DS20002321C-page 1
MCP6491/2/4
Typical Application
C
2
R
2
V
OUT
I
D1
–
Light
D
1
MCP649X
+
V
DD
Photodiode Amplifier
DS20002321C-page 2
2012-2013 Microchip Technology Inc.
MCP6491/2/4
1.0
1.1
ELECTRICAL
CHARACTERISTICS
Absolute Maximum Ratings †
V
DD
– V
SS
................................................................................................................................... ......................................................6.5V
Current at Input Pins ................................................................................................................ ......................................................±2 mA
Analog Inputs (V
IN
+, V
IN
-) (Note
1)
.................................................................................................................V
SS
– 1.0V to V
DD
+ 1.0V
All Other Inputs and Outputs ...........................................................................................................................V
SS
– 0.3V to V
DD
+ 0.3V
Difference Input Voltage...........................................................................................................................................................V
DD
– V
SS
Output Short-Circuit Current ................................................................................................................ ...................................continuous
Current at Output and Supply Pins ............................................................................................................... ..............................±60 mA
Storage Temperature ................................................................................................................ .....................................-65°C to +150°C
Maximum Junction Temperature (T
J
) ................................................................................................................ ...........................+150°C
ESD protection on all pins (HBM)
4 kV
Note 1:
See
Section 4.1.2, Input Voltage Limits.
† Notice:
Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device.
This is a stress rating only and functional operation of the device at those or any other conditions above those indicated
in the operational listings of this specification is not implied. Exposure to maximum rating conditions for extended
periods may affect device reliability.
1.2
Specifications
DC ELECTRICAL SPECIFICATIONS
TABLE 1-1:
Electrical Characteristics:
Unless otherwise indicated, V
DD
= +2.4V to +5.5V, V
SS
= GND, T
A
= +25°C,
V
CM
= V
DD
/2, V
OUT
V
DD
/2, V
L
= V
DD
/2 and R
L
= 10 kto V
L
. (Refer to
Figure 1-1).
Parameters
Input Offset
Input Offset Voltage
Input Offset Drift with Temperature
Power Supply Rejection Ratio
Input Bias Current and Impedance
Input Bias Current
I
B
—
—
—
Input Offset Current
Common Mode Input Impedance
Differential Input Impedance
Common Mode
Common Mode Input Voltage
Range
Common Mode Rejection Ratio
V
CMR
CMRR
V
SS
- 0.3
65
70
Open-Loop Gain
DC Open-Loop Gain (Large Signal)
A
OL
95
115
—
dB
0.2V < V
OUT
<(V
DD
– 0.2V)
V
DD
= 5.5V, V
CM
= V
SS
—
84
88
V
DD
+ 0.3
—
—
V
dB
dB
V
CM
= -0.3V to 2.7V,
V
DD
= 2.4V
V
CM
= -0.3V to 5.8V,
V
DD
= 5.5V
I
OS
Z
CM
Z
DIFF
—
—
—
±1
8
150
±0.1
10
13
||6
10
13
||6
—
—
350
—
—
—
pA
pA
pA
pA
||pF
||pF
T
A
= +85°C
T
A
= +125°C
V
OS
V
OS
/T
A
PSRR
-1.5
—
75
—
±2.5
90
+1.5
—
—
mV
dB
V
DD
= 3.0V, V
CM
= V
DD
/4
V
CM
= V
DD
/4
µV/°C T
A
= -40°C to +125°C
Sym
Min
Typ
Max
Units
Conditions
2012-2013 Microchip Technology Inc.
DS20002321C-page 3
MCP6491/2/4
TABLE 1-1:
DC ELECTRICAL SPECIFICATIONS (CONTINUED)
Electrical Characteristics:
Unless otherwise indicated, V
DD
= +2.4V to +5.5V, V
SS
= GND, T
A
= +25°C,
V
CM
= V
DD
/2, V
OUT
V
DD
/2, V
L
= V
DD
/2 and R
L
= 10 kto V
L
. (Refer to
Figure 1-1).
Parameters
Output
High-Level Output Voltage
V
OH
2.380
5.480
Low-Level Output Voltage
V
OL
—
—
Output Short-Circuit Current
Power Supply
Supply Voltage
Quiescent Current per Amplifier
V
DD
I
Q
2.4
200
—
530
5.5
800
V
µA
I
O
= 0, V
CM
= V
DD
/4
I
SC
—
—
2.396
5.493
0.004
0.007
±15
±40
—
—
0.020
0.020
—
—
V
V
V
V
mA
mA
V
DD
= 2.4V
0.5V input overdrive
V
DD
= 5.5V
0.5V input overdrive
V
DD
= 2.4V
0.5 V input overdrive
V
DD
= 5.5V
0.5 V input overdrive
V
DD
= 2.4V
V
DD
= 5.5V
Sym
Min
Typ
Max
Units
Conditions
TABLE 1-2:
AC ELECTRICAL SPECIFICATIONS
Electrical Characteristics:
Unless otherwise indicated, T
A
= +25°C, V
DD
= +2.4V to +5.5V, V
SS
= GND,
V
CM
= V
DD
/2, V
OUT
V
DD
/2, V
L
= V
DD
/2, R
L
= 10 kto V
L
and C
L
= 20 pF. (Refer to
Figure 1-1).
Parameters
AC Response
Gain Bandwidth Product
Phase Margin
Slew Rate
Noise
Input Noise Voltage
Input Noise Voltage Density
Input Noise Current Density
E
ni
e
ni
i
ni
—
—
—
—
6
19
14
0.6
—
—
—
—
µVp-p
nV/Hz
nV/Hz
fA/Hz
f = 0.1 Hz to 10 Hz
f = 1 kHz
f = 10 kHz
f = 1 kHz
GBWP
PM
SR
—
—
—
7.5
57
6
—
—
—
MHz
°
V/µs
G = +1V/V
Sym
Min
Typ
Max
Units
Conditions
TABLE 1-3:
TEMPERATURE SPECIFICATIONS
Parameters
Sym
T
A
T
A
JA
JA
JA
JA
JA
JA
JA
Min
-40
-65
—
—
—
—
—
—
—
Typ
—
—
331
256
52.5
211
149.5
95.3
100
Max
+125
+150
—
—
—
—
—
—
—
Units
°C
°C
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
Conditions
Note 1
Electrical Characteristics:
Unless otherwise indicated, V
DD
= +2.4V to +5.5V and V
SS
= GND.
Temperature Ranges
Operating Temperature Range
Storage Temperature Range
Thermal Package Resistances
Thermal Resistance, 5L-SC-70
Thermal Resistance, 5L-SOT-23
Thermal Resistance, 8L-2x3 TDFN
Thermal Resistance, 8L-MSOP
Thermal Resistance, 8L-SOIC
Thermal Resistance, 14L-SOIC
Thermal Resistance, 14L-TSSOP
Note 1:
The internal junction temperature (T
J
) must not exceed the absolute maximum specification of +150°C.
DS20002321C-page 4
2012-2013 Microchip Technology Inc.
MCP6491/2/4
1.3
Test Circuits
C
F
6.8 pF
R
G
100 k
V
P
V
IN+
MCP649X
V
IN–
V
M
R
G
100 k
R
F
100 k
C
F
6.8 pF
R
L
10 k
V
OUT
C
L
20 pF
C
B1
100 nF
R
F
100 k
V
DD
C
B2
1 µF
V
DD
/2
The circuit used for most DC and AC tests is shown in
Figure 1-1.
This circuit can independently set V
CM
and
V
OUT
(refer to
Equation 1-1).
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
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.
2012-2013 Microchip Technology Inc.
DS20002321C-page 5