voltage ranges include ground
Low supply current: 80 μA maximum
High output drive: 5 mA minimum
Low offset voltage: 1.0 mV maximum
High open-loop gain: 800 V/mV typical
Industry-standard quad pinouts
Quad Operational Amplifier
OP490
FUNCTIONAL BLOCK DIAGRAMS
1
OUT A
2
–IN A
3
+IN A
4
V+
OP490
5
+IN B
6
–IN B
7
OUT B
TOP VIEW
(Not to Scale)
Figure 1. 14-Lead Plastic DIP
(P-Suffix)
1
OUT A
2
–IN A
3
+IN A
4
V+
OP490
5
+IN B
6
–IN B
7
OUT B
TOP VIEW
8
NC
(Not to Scale)
NC = NO CONNECT
Figure 2. 16-Lead SOIC
(S-Suffix)
14
13
12
11
10
16
15
14
13
12
10
9
8
11
9
OUT D
–IN D
+IN D
V–
+IN C
–IN C
OUT C
OUT D
–IN D
+IN D
V–
+IN C
–IN C
OUT C
NC
00308-001
00308-002
GENERAL DESCRIPTION
The OP490 is a high performance micropower quad op amp
that operates from a single supply of 1.6 V to 36 V or from dual
supplies of ±0.8 V to ±18 V. The input voltage range includes
the negative rail allowing the OP490 to accommodate input
signals down to ground in single-supply operation. The output
swing of the OP490 also includes ground when operating from
a single supply, enabling zero-in, zero-out operation.
The quad OP490 draws less than 20 μA of quiescent supply
current per amplifier, but each amplifier is able to deliver over
5 mA of output current to a load. Input offset voltage is under
0.5 mV. Gain exceeds over 400,000 and CMR is better than
90 dB. A PSRR of under 5.6 μV/V minimizes offset voltage
changes experienced in battery-powered systems.
The quad OP490 combines high performance with the space
and cost savings of quad amplifiers. The minimal voltage and
current requirements of the OP490 make it ideal for battery and
solar-powered applications, such as portable instruments and
remote sensors.
Rev. E
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
@ VS = ±1.5 V to ±15 V, TA = 25°C, unless otherwise noted.
Table 1.
Parameter Symbol Conditions Min Typ Max Unit
INPUT CHARACTERISTICS
Input Offset Voltage VOS 0.6 1.0 mV
Input Offset Current IOS VCM = 0 V 0.4 5 nA
Input Bias Current IB V
Large Signal Voltage Gain AVO V
R
R
R
V+ = 5 V, V− = 0 V, 1 V < VO < 4 V
R
R
Input Voltage Range1 IVR V+ = 5 V, V− = 0 V 0 4 V
Common-Mode Rejection Ratio CMRR V+ = 5 V, V− = 0 V, 0 V < VCM < 4 V 80 100 dB
V
Input Resistance Differential Mode RIN VS = ±15 V 30 MΩ
Input Resistance Common-Mode R
VS = ±15 V 20 GΩ
INCM
OUTPUT CHARACTERISTICS
Output Voltage Swing VO L V
V
Output Voltage High VOH V+ = 5 V, V− = 0 V, RL = 2 kΩ 4.0 4.2 V
Output Voltage Low VOL V+ = 5 V, V− = 0 V, RL = 10 kΩ 100 500 μV
Capacitive Load Stability AV = 1 650 pF
DYNAMIC PERFORMANCE
Slew Rate SR VS = ±15 V 5 12 V/ms
Channel Separation2 CS fO = 10 Hz, VO = 20 V p-p, VS = ±15 V 120 150 dB
Gain Bandwidth Product GBWP AV = 1 20 kHz
POWER SUPPLY
Power Supply Rejection Ratio PSRR 3.2 10 μV/V
Supply Current (All Amplifiers) ISY VS = ±1.5 V, no load 40 60 μA
V
NOISE PERFORMANCE
Voltage Noise en p-p fO = 0.1 Hz to 10 Hz, VS = ±15 V 3 μV p-p
Voltage Noise Density en f = 1 kHz 60 nV/√Hz
Current Noise Density in f = 1 kHz 0.07 pA/√Hz
1
Guaranteed by CMRR test.
2
Guaranteed but not 100% tested.
= 0 V 4.2 25 nA
CM
= ±15 V, VO = ±10 V
S
= 100 kΩ 400 800 V/mV
L
= 10 kΩ 200 400 V/mV
L
= 2 kΩ 100 200 V/mV
L
= 100 kΩ 100 250 V/mV
L
= 10 kΩ 70 140 V/mV
L
= ±15 V, −15 V < VCM < +13.5 V 90 120 dB
S
= ±15 V, RL = 10 kΩ ±13.5 ±14.2 V
S
= ±15 V, RL = 2 kΩ ±10.5 ±11.5 V
S
= ±15 V, no load 60 80 μA
S
Rev. E | Page 3 of 16
Page 4
OP490
–
V
@ VS = ±1.5 V to ±15 V, −40°C ≤ TA ≤ +85°C
Table 2.
Parameter Symbol Conditions Min Typ Max Unit
INPUT CHARACTERISTICS
Input Offset Voltage V
Average Input Offset Voltage Drift TCVOS VS = ±15 V 4 μV/°C
Input Offset Current IOS VCM = 0 V 1.3 7 nA
Input Bias Current IB VCM = 0 V 4.4 25 nA
Large Signal Voltage Gain AVO VS = ±15 V, VO = ±10 V
R
R
R
V+ = 5 V, V− = 0 V, 1 V < VO < 4 V
R
R
Input Voltage Range1 IVR V+ = 5 V, V− = 0 V 0.3 5 V
−15 +13.5 V
Common-Mode Rejection Ratio CMRR V+ = 5 V, V− = 0 V, 0 V < VCM < 3.5 V 80 100 dB
V
OUTPUT CHARACTERISTICS
Output Voltage Swing VO VS = ±15 V ±13 ±14 V
R
Output Voltage High VOH V+ = 5 V, V− = 0 V, RL = 2 kΩ 3.9 4.1 V
Output Voltage Low VOL V+ = 5 V, V− = 0 V, RL = 10 kΩ 100 500 μV
POWER SUPPLY
Power Supply Rejection Ratio PSRR 5.6 17.8 μV/V
Supply Current (All Amplifiers) ISY V
V
1
Guaranteed by CMRR test.
0.8 1.5 mV
OS
= 100 kΩ 300 600 V/mV
L
= 10 kΩ 150 250 V/mV
L
= 2 kΩ 75 125 V/mV
L
= 100 kΩ 80 160 V/mV
L
= 10 kΩ 40 90 V/mV
L
= ±15 V, −15 V < VCM < +13.5 V 90 110 dB
S
= 2 kΩ ±10 ±11 V
L
= ±1.5 V, no load 60 100 mA
S
= ±15 V, no load 75 120 mA
S
+
+IN
IN
Figure 3. Simplified Schematic
Rev. E | Page 4 of 16
OUTPUT
V–
00308-003
Page 5
OP490
ABSOLUTE MAXIMUM RATINGS
Table 3.
Parameter Rating
Supply Voltage ±18 V
Digital Input Voltage [(V−) − 20 V] to [(V+) + 20 V]
Common-Mode Input Voltage [(V−) − 20 V] to [(V+) + 20 V]
Output Short-Circuit Duration Continuous
Storage Temperature Range −65°C to +150°C
Operating Temperature Range −40°C to +85°C
Junction Temperature (TJ) Range −65°C to +150°C
Lead Temperature (Soldering,
60 sec)
300°C
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
THERMAL RESISTANCE
θJA is specified for worst-case mounting conditions, that is, θJA is
specified for a device in socket for the PDIP package; θ
is
JA
specified for a device soldered to a printed circuit board (PCB)
for the SOIC package.
Figure 8. Open-Loop Gain vs. Single-Supply Voltage
140
VS = ±15V
T
= 25°C
A
120
R
= 10k
L
100
80
60
40
OPEN-LOOP GAIN (dB)
20
GAIN
PHASE
0
45
90
135
180
PHASE SHIFT ( Deg rees)
3.6
–75–50–252550751250
TEMPERATURE ( °C)
Figure 6. Input Bias Current vs. Temperature
00308-006
Rev. E | Page 6 of 16
0
0.11101001k10k100k
FREQUENCY (Hz)
Figure 9. Open-Loop Gain and Phase Shift vs. Frequency
00308-009
Page 7
OP490
60
VS = ±15V
T
= 25°C
A
40
20
CLOSED-LOOP GAIN (dB)
0
120
TA = 25°C
100
80
60
40
POWER SUPP LY REJECTION (dB)
POSITIVE SUPPLY
NEGATIVE SUPPLY
–20
101001k10k100k
FREQUENCY (Hz)
Figure 10. Closed-Loop Gain vs. Frequency
6
V+ = 5V, V– = 0V
T
= 25°C
A
5
4
3
2
OUTPUT VOLT AGE SWING (V)
1
0
1001k10k100k
LOAD RESISTANCE ()
Figure 11. Output Voltage Swing vs. Load Resistance
16
VS = ±15V
T
= 25°C
A
14
12
POSITIVE
10
20
00308-010
1101001k
LOAD RESISTANCE ()
00308-013
Figure 13. Power Supply Rejection vs. Frequency
140
120
100
80
60
COMMON-MODE REJECTION (dB)
40
00308-011
0.11101001k
FREQUENCY (Hz)
VS = ±15V
T
= 25°C
A
00308-014
Figure 14. Common-Mode Rejection vs. Frequency
1k
100
VS = ±15V
T
= 25°C
A
8
6
OUTPUT SWING (V)
4
2
0
1001k10k100k
NEGATIVE
LOAD RESISTANCE ()
Figure 12. Output Voltage Swing vs. Load Resistance
00308-012
Rev. E | Page 7 of 16
10
VOLTAG E NOISE DENSI T Y (nV/ Hz)
1
0.11101001k
FREQUENCY (Hz)
Figure 15. Voltage Noise Density vs. Frequency
00308-015
Page 8
OP490
100
10
VS = ±15V
T
= 25°C
A
VS = ±15V
T
= 25°C
A
A
= 1
V
R
= 10k
L
C
= 500pF
L
1
CURRENT NOISE DENSITY (pA/ Hz)
0.1
0.11101001k
FREQUENCY (Hz)
Figure 16. Current Noise Density vs. Frequency
00308-016
VOLTAGE (5V/DIV)
TIME (1ms/DIV)
00308-018
Figure 18. Large Signal Transient Response
VS = ±15V
T
= 25°C
A
A
= 1
V
R
= 10k
L
C
= 500pF
L
VOLTAGE (20mV/DIV)
TIME ( 100µs/DIV)
00308-017
Figure 17. Small Signal Transient Response
Rev. E | Page 8 of 16
Page 9
OP490
V
–18V
V
APPLICATIONS INFORMATION
BATTERY-POWERED APPLICATIONS
The OP490 can be operated on a minimum supply voltage of
141312111098
DC
AB
12345 67
GND
+18
00308-019
Figure 19. Burn-In Circuit
+15
+15V
+
1/4
1k
V
IN
OP490
A
–
–15V
+
1/4
OP490
B
–
10010k
+
OP37
A
–
–15V
V1
20V p-p @ 10Hz
V2
1.6 V or with dual supplies of ±0.8 V drawing only 60 μA of
supply current. In many battery-powered circuits, the OP490
can be continuously operated for hundreds of hours before
requiring battery replacement, thereby reducing equipment
downtime and operating costs.
High performance portable equipment and instruments
frequently use lithium cells because of their long shelf life, light
weight, and high energy density relative to older primary cells.
Most lithium cells have a nominal output voltage of 3 V and are
noted for a flat discharge characteristic. The low supply current
requirement of the OP490, combined with the flat discharge
characteristic of the lithium cell, indicates that the OP490 can
be operated over the entire useful life of the cell. Figure 21
shows the typical discharge characteristic of a 1 Ah lithium cell
powering an OP490 with each amplifier, in turn, driving full
output swing into a 100 kΩ load.
4
3
2
1
+
1/4
OP490
C
–
+
1/4
OP490
D
–
CHANNEL SEPARATI ON = 20 log
Figure 20. Channel Separation Test Circuit
V1
V2/1000
00308-020
Rev. E | Page 9 of 16
LITHIUM-SULPHUR DIOXIDE CELL VOLTAGE (V)
0
0250500100012501500750
HOURS
00308-021
Figure 21. Lithium-Sulphur Dioxide Cell Discharge Characteristic with
OP490 and 100 kΩ Loads
SINGLE-SUPPLY OUTPUT VOLTAGE RANGE
In single-supply operation the input and output ranges of the
OP490 include ground. This allows true zero-in, zero-out
operation. The output stage provides an active pull-down to
around 0.8 V above ground. Below this level, a load resistance of up
to 1 MΩ to ground is required to pull the output down to zero.
In the region from ground to 0.8 V, the OP490 has voltage gain
equal to the data sheet specification. Output current source
capability is maintained over the entire voltage range including
ground.
Page 10
OP490
INPUT VOLTAGE PROTECTION
The OP490 uses a PNP input stage with protection resistors in
series with the inverting and noninverting inputs. The high
breakdown of the PNP transistors coupled with the protection
resistors provides a large amount of input protection, allowing
the inputs to be taken 20 V beyond either supply without
damaging the amplifier.
MICROPOWER VOLTAGE-CONTROLLED
OSCILLATOR
An OP490 in combination with an inexpensive quad CMOS
switch comprise the precision V
provides triangle and square wave outputs and draws only 75 μA
from a 5 V supply. A acts as an integrator; S1 switches the
R1
200k
V
CONTROL
R2
200k
100k
of Figure 22. This circuit
CO
75nF
+15V
–
2
1/4
OP490
+
A
3
R4
R3
200k
C1
4
1
11
TRIANGLE
OUT
charging current symmetrically to yield positive and negative
ramps. The integrator is bounded by B, which acts as a Schmitt
trigger with a precise hysteresis of 1.67 V, set by Resistors R5,
R6, and R7, and the associated CMOS switches. The resulting
output of A is a triangle wave with upper and lower levels of
3.33 V and 1.67 V. The output of B is a square wave with almost
rail-to-rail swing. With the components shown, frequency of
operation is given by the equation
f
OUT
= V
(Volts) × 10 Hz/V
CONTROL
but this is easily changed by varying C1. The circuit operates
well up to a few hundred hertz.
+15V
R5
200k
–
6
R8
200k
+5V
5
1/4
OP490
+
7
B
SQUARE
OUT
IN/OUT
114
OUT/IN
213
OUT/IN
312
IN/OUT
411
CONT
510
CONT
69
V
SS
78
S1
S2
S3
S4
V
CONT
CONT
IN/OUT
OUT/IN
OUT/IN
IN/OUT
DD
+5V
+5V
R6
200k
R7
200k
Figure 22. Micropower Voltage Controlled Oscillator
The circuit shown in Figure 23 uses the DAC8408 CMOS quad
8-bit DAC, and the OP490 to form a single-supply quad voltage
output DAC with a supply drain of only 140 μA. The DAC8408
is used in voltage switching mode and each DAC has an output
resistance (≈10 kΩ) independent of the digital input code. The
output amplifiers act as buffers to avoid loading the DACs. The
100 kΩ resistors ensure that the OP490 outputs swing below 0.8 V
when required.
+5
4
REFERENCE
VOLTAGE
1.5V
25
4
5
6
I
OUT1A
I
OUT2A/2B
I
OUT1B
I
OUT1C
DAC A
1/4
DAC8408
DAC B
1/4
DAC8408
DAC C
1/4
DAC8408
2
V
A
2
REF
B
V
8
REF
C
V
REF
27
3
6
5
13
12
–
1/4
OP490
+
A
–
1/4
OP490
+
B
–
1/4
OP490
+
C
1
11
7
14
R1
100k
R2
100k
R3
100k
V
A
OUT
V
B
OUT
V
C
OUT
I
24
DAC DATA BUS
PIN 9 (LSB) TO PIN 16 (MSB)
DIGITAL
CONTROL
SIGNALS
23
17
18
19
20
OUT2C/2D
I
OUT1D
A/B
R/W
DS1
DS2
DAC D
1/4
DAC8408
DAC8408
DGND
28
D
V
REF
9
1021
–
1/4
OP490
+
D
8
R4
100k
V
D
OUT
OP490
00308-023
Figure 23. Micropower Single-Supply Quad Voltage Output 8-Bit DAC
Rev. E | Page 11 of 16
Page 12
OP490
+15V
R1
1k
2
–
4
1/4
OP490
3
V
IN
+
–15V
1
A
11
R2
9k
–
6
OP490
+
5
1/4
R3
50
7
B
Figure 24. High Output Amplifier
HIGH OUTPUT AMPLIFIER
The amplifier shown in Figure 24 is capable of driving 25 V p-p
into a 1 kΩ load. Design of the amplifier is based on a bridge
configuration. A amplifies the input signal and drives the load
with the help of B. Amplifier C is a unity-gain inverter which
drives the load with help from D. Gain of the high output
amplifier with the component values shown is 10, but can easily
be changed by varying R1 or R2.
SINGLE-SUPPLY MICROPOWER QUAD
PROGRAMMABLE GAIN AMPLIFIER
The combination of a quad OP490 and the DAC8408 quad 8-bit
CMOS DAC creates a quad programmable-gain amplifier with
a quiescent supply drain of only 140 μA. The digital code
present at the DAC, which is easily set by a microprocessor,
R4
50
R5
5k
R6
5k
9
R7
50
–
R
R8
L
50
14
1/4
OP490
D
13
+
12
8
1/4
OP490
C
–
10
+
00308-024
determines the ratio between the fixed DAC feedback resistor
and the resistance of the DAC ladder seen by the op amp feedback loop. The gain of each amplifier is:
V
OUT
256
−=
IN
nV
where n equals the decimal equivalent of the 8-bit digital code
present at the DAC. If the digital code present at the DAC
consists of all zeros, the feedback loop opens causing the op
amp output to saturate. The 10 MΩ resistors placed in parallel
with the DAC feedback loop eliminate this problem with a very
small reduction in gain accuracy. The 2.5 V reference biases the
amplifiers to the center of the linear region providing maximum
output swing.
Rev. E | Page 12 of 16
Page 13
OP490
V
1
VINA
VINB
C1
0.1µF
C2
0.1µF
DD
R
A
3
FB
DAC A
1/4
DAC8408
B
R
7
FB
V
REF
I
OUT1A
I
OUT2A/2B
V
REF
A
2
R1
10M
4
5
B
8
2
–
1/4
OP490
3
+
A
+5V
4
1
11
V
A
OUT
R2
10M
6
27
R3
10M
25
24
21
R4
10M
23
6
–
1/4
OP490
5
+
B
9
–
1/4
OP490
10
13
+
C
–
1/4
OP490
12
+
D
7
8
14
V
B
OUT
V
C
OUT
V
D
OUT
OP490
+2.5V
REFERENCE
VOLTAGE
00308-025
VINC
VIND
DIGITAL
CONTROL
SIGNALS
C3
0.1µF
C4
0.1µF
C
R
25
FB
D
R
22
FB
DAC DATA BUS
PIN 9 (LSB) TO PIN 16 (MSB)
17
A/B
18
R/W
19
DS1
20
DS2
DAC B
DAC8408
DAC C
DAC8408
DAC D
DAC8408
DAC8408
DGND
1/4
1/4
1/4
I
OUT1B
C
V
REF
I
OUT1C
I
OUT2C/2D
V
D
REF
I
OUT1D
28
Figure 25. Single-Supply Micropower Quad Programmable Gain Amplifier
Rev. E | Page 13 of 16
Page 14
OP490
C
OUTLINE DIMENSIONS
0.775 (19.69)
0.750 (19.05)
0.735 (18.67)
0.210 (5.33)
0.150 (3.81)
0.130 (3.30)
0.110 (2.79)
0.022 (0.56)
0.018 (0.46)
0.014 (0.36)
MAX
14
1
0.100 (2.54)
BSC
0.070 (1.78)
0.050 (1.27)
0.045 (1.14)
8
7
0.280 (7. 11)
0.250 (6.35)
0.240 (6.10)
0.015
(0.38)
MIN
SEATING
PLANE
0.005 (0.13)
MIN
0.060 (1.52)
MAX
0.015 (0.38)
GAUGE
PLANE
0.325 (8.26)
0.310 (7.87)
0.300 (7.62)
0.430 (10.92)
MAX
0.195 (4.95)
0.130 (3.30)
0.115 (2.92)
0.014 (0.36)
0.010 (0.25)
0.008 (0.20)
CONTROLL ING DIMENSIONS ARE IN INCHES; MILLIMET E R DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF INCH EQUIVALENTS F OR
REFERENCE ON LY AND ARE NOT APPROPRIATE FOR USE IN DES IGN.
CORNER LEADS M AY BE CONFIGURED AS WHOLE OR HALF LEADS.
CONTROLL ING DIMENSIONS ARE IN MILLI METERS; I NCH DI M E NS IONS
(IN PARENTHESES) ARE ROUNDED-OFF M ILLIM E TER EQUIVALENTS FOR
REFERENCE ON LY AND ARE NOT APPROPRIATE FOR USE IN DE SIGN.
COMPLIANT TO JEDEC STANDARDS MS-013-AA
Figure 27. 16-Lead Standard Small Outline Package [SOIC_W]
Dimensions shown in millimeters and (inches)
Rev. E | Page 14 of 16
Page 15
OP490
ORDERING GUIDE
Model1 Temperature Range Package Description Package Option
OP490GP −40°C to +85°C 14-Lead PDIP_N N-14 (P-Suffix)
OP490GPZ −40°C to +85°C 14-Lead PDIP_N N-14 (P-Suffix)
OP490GS −40°C to +85°C 16-Lead SOIC_W RW-16 (S-Suffix)
OP490GSZ −40°C to +85°C 16-Lead SOIC_W RW-16 (S-Suffix)
OP490GSZ-REEL −40°C to +85°C 16-Lead SOIC_W RW-16 (S-Suffix)