Page 1
36 V Precision, 2.8 nV/√Hz
FEATURES
Very low voltage noise: 2.8 nV/√Hz
Rail-to-rail output swing
Low input bias current: 2 nA maximum
Very low offset voltage: 75 μV maximum
Low input offset drift: 0.6 μV/°C maximum
Very high gain: 120 dB
Wide bandwidth: 10 MHz typical
±5 V to ±18 V operation
APPLICATIONS
Precision instrumentation
PLL filters
Laser diode control loops
Strain gage amplifiers
Medical instrumentation
Thermocouple amplifiers
GENERAL DESCRIPTION
The AD8675 precision operational amplifier has ultralow offset,
drift, and voltage noise combined with very low input bias
currents over the full operating temperature range. The AD8675
is a precision, wide bandwidth op amp featuring rail-to-rail
output swings and very low noise. Operation is fully specified
from ±5 V to ±15 V.
The AD8675 features a rail-to-rail output like that of the
but with wide bandwidth and even lower voltage noise, combined with the precision and low power consumption like that
of the industry-standard OP07 amplifier. Unlike other low
noise, rail-to-rail op amps, the AD8675 has very low input bias
current and low input current noise.
With typical offset voltage of only 10 µV, offset drift of 0.2 µV/°C,
and noise of only 0.10 V p-p (0.1 Hz to 10 Hz), the AD8675 is
perfectly suited for applications where large error sources
cannot be tolerated. For applications with even lower offset
tolerances, the proprietary nulling capability allows a combination
of both device and system offset errors up to 3.5 mV (referred
OP184,
Rail-to-Rail Output Op Amp
AD8675
PIN CONFIGURATIONS
1
NULL
–IN
+IN
V–
NULL
–IN
+IN
V–
AD8675
2
3
TOP VIEW
(Not to Scale)
4
NC = NO CONNECT
Figure 1. 8-Lead SOIC_N (R-8)
1
AD8675
2
TOP VIEW
3
(Not to Scale)
4
NC = NO CONNECT
Figure 2. 8-Lead MSOP (RM-8)
to the input) to be compensated externally. Unlike previous
circuits, the AD8675 accommodates this adjustment without
adversely affecting the offset drift, CMRR, and PSRR of the
amplifier. Precision instrumentation, PLL, and other precision
filter circuits, position and pressure sensors, medical instrumentation, and strain gage amplifiers benefit greatly from the very
low noise, low input bias current, and wide bandwidth. Many
systems can take advantage of the low noise, dc precision, and
rail-to-rail output swing provided by the AD8675 to maximize
SNR and dynamic range.
The smaller packages and low power consumption afforded by
the AD8675 allow maximum channel density or minimum
board size for space-critical equipment.
The AD8675 is specified for the extended industrial temperature
range (−40°C to +125°C). The AD8675 amplifier is available in
the tiny 8-lead MSOP, and the popular 8-lead, narrow SOIC,
RoHS compliant packages. MSOP packaged devices are only
available in tape and reel format.
8
7
6
5
8
7
6
5
NULL
V+
OUT
NC
NULL
V+
OUT
NC
05564-001
05564-002
Rev. A
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Anal og Devices for its use, nor for any infringements of patents or ot her
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.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700 www.analog.com
Fax: 781.461.3113 ©2005-2007 Analog Devices, Inc. All rights reserved.
Page 2
AD8675
TABLE OF CONTENTS
Features.............................................................................................. 1
Applications....................................................................................... 1
Pin Configurations ........................................................................... 1
General Description ......................................................................... 1
Revision History ............................................................................... 2
Specifications..................................................................................... 3
Electrical Specifications............................................................... 3
REVISION HISTORY
4/07—Rev. 0 to Rev. A
Inserted Figure 7 and Figure 8;
renumbered sequentially ................................................................. 6
10/05—Revision 0: Initial Version
Absolute Maximum Ratings ............................................................5
Thermal Resistance.......................................................................5
ESD Caution...................................................................................5
Typical Performance Characteristics..............................................6
Outline Dimensions....................................................................... 11
Ordering Guide .......................................................................... 11
Rev. A | Page 2 of 12
Page 3
AD8675
SPECIFICATIONS
ELECTRICAL SPECIFICATIONS
VS = ±5.0 V, VCM = 0 V, VO = 0 V, TA = +25°C, unless otherwise specified.
Table 1.
Parameter Symbol Conditions Min Typ Max Unit
INPUT CHARACTERISTICS
Offset Voltage VOS 10 75 μV
−40°C ≤ TA ≤ +125°C 12 240
Input Bias Current IB −2 0.5 2 nA
−40°C ≤ TA ≤ +125°C −5.5 −2 5.5 nA
Input Offset Current IOS −1 0.1 1 nA
−40°C ≤ TA ≤ +125°C −2.8 0.1 2.8 nA
Input Voltage Range −3.5 3.5 V
Common-Mode Rejection Ratio CMRR VCM = −3.5 V to +3.5 V 105 130 dB
−40°C ≤ TA ≤ +125°C 105 130 dB
Open-Loop Gain AVO R
V
−40°C ≤ TA ≤ +125°C 700 1250 V/mV
Offset Voltage Drift ΔVOS/ΔT −40°C ≤ TA ≤ +125°C 0.2 0.6 μV/°C
OUTPUT CHARACTERISTICS
Output Voltage High VOH R
−40°C ≤ TA ≤ +125°C 4.82 4.85 V
Output Voltage Low VOL R
−40°C ≤ TA ≤ +125°C −4.91 −4.82 V
Short-Circuit Limit ISC 40 mA
Output Current IO ±20 mA
POWER SUPPLY
Power Supply Rejection Ratio PSRR VS = ±5.0 V to ±15.0 V 120 140 dB
−40°C ≤ TA ≤ +125°C 120 140 dB
Supply Current/Amplifier ISY V
−40°C ≤ TA ≤ +125°C 2.7 3.4 mA
DYNAMIC PERFORMANCE
Slew Rate SR RL = 2 kΩ 2.5 V/μs
Gain Bandwidth Product GBP 10 MHz
NOISE PERFORMANCE
Voltage Noise e
0.1 Hz to 10 Hz 0.1 μV p-p
n p-p
Voltage Noise Density en f = 1 kHz 2.8 nV/√Hz
Current Noise Density in f = 10 Hz 0.3 pA/√Hz
= 2 kΩ to ground, 1000 2000 V/mV
L
= −4.0 V to +4.0 V
O
= 2 kΩ to ground 4.86 4.90 V
L
= 2 kΩ to ground −4.91 −4.86 V
L
= 0 V 2.3 2.7 mA
O
Rev. A | Page 3 of 12
Page 4
AD8675
VS = ±15 V, VCM = 0 V, VO = 0 V, TA = +25°C, unless otherwise specified.
Table 2.
Parameter Symbol Conditions Min Typ Max Units
INPUT CHARACTERISTICS
Offset Voltage VOS 10 75 μV
−40°C ≤ TA ≤ +125°C 12 240
Input Bias Current IB −2 0.5 2 nA
−40°C ≤ TA ≤ +125°C −4.5 1 4.5 nA
Input Offset Current IOS −1 0.1 1 nA
−40°C ≤ TA ≤ +125°C −2.8 0.1 2.8 nA
Input Voltage Range −13.5 13.5 V
Common-Mode Rejection Ratio CMRR VCM = −12.5 V to +12.5 V 114 130 dB
−40°C ≤ TA ≤ +125°C 114 130 dB
Open-Loop Gain AVO R
V
−40°C ≤ TA ≤ +125°C 700 1700 V/mV
Offset Voltage Drift ΔVOS/ΔT −40°C ≤ TA ≤ +125°C 0.2 0.6 μV/°C
OUTPUT CHARACTERISTICS
Output Voltage High VOH SOIC RL: 2 kΩ to ground 14.75 14.8 V
MSOP RL: 2 kΩ to ground 14.67 14.78 V
SOIC −40°C ≤ TA ≤ +125°C 14.69 14.75 V
MSOP −40°C ≤ TA ≤ +125°C 14.3 14.66 V
Output Voltage Low VOL R
−40°C ≤ TA ≤ +125°C −14.78 −14.69 V
Short-Circuit Limit ISC 40 mA
Output Current IO ±20 mA
POWER SUPPLY
Power Supply Rejection Ratio PSRR VS = ±5.0 V to ±15.0 V 120 140 dB
−40°C ≤ TA ≤ +125°C 120 140 dB
Supply Current/Amplifier ISY V
−40°C ≤ TA ≤ +125°C 2.9 3.8 mA
DYNAMIC PERFORMANCE
Slew Rate SR RL =10 kΩ 2.5 V/μs
Gain Bandwidth Product GBP 10 MHz
NOISE PERFORMANCE
Voltage Noise e
0.1 Hz to 10 Hz 0.1 μV p-p
n p-p
Voltage Noise Density en f = 1 kHz 2.8 nV/√Hz
Current Noise Density in f = 10 Hz 0.3 pA/√Hz
= 2 kΩ to ground, 1500 4000 V/mV
L
= −14.0 V to +14.0 V
O
= 2 kΩ to ground −14.85 −14.75 V
L
= 0 V 2.5 2.9 mA
O
Rev. A | Page 4 of 12
Page 5
AD8675
ABSOLUTE MAXIMUM RATINGS
Tab l e 3.
Parameter Rating
Supply Voltage ±18 V
Input Voltage ±V supply
Differential Input Voltage ±0.7 V
Output Short-Circuit Duration to GND Indefinite
Storage Temperature Range
RM-8, R-8 Packages −65°C to +150°C
Operating Temperature Range −40°C to +125°C
Junction Temperature Range
RM-8, R-8 Packages −65°C to +150°C
Lead Temperature Range (Soldering, 10 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
Table 4. Thermal Resistance
Package Type θJA θ
8-Lead MSOP (RM-8) 210 45 °C/W
8-Lead SOIC_N (R-8) 158 43 °C/W
Unit
JC
ESD CAUTION
Rev. A | Page 5 of 12
Page 6
AD8675
TYPICAL PERFORMANCE CHARACTERISTICS
±15 V and ±5 V, TA = 25°C, unless otherwise specified.
10
9
8
7
6
5
4
3
2
VOLTAGE NOISE DENSITY (nV/ Hz)
1
0
1 10 100 1k 10k 100k
FREQUENCY (Hz)
Figure 3. Voltage Noise Density vs. Frequency
50
45
40
35
30
25
20
15
NUMBER OF AMPLIFIERS
10
5
0
–30
–25
–20
–15
0
5
–5
–10
OFFSET VOLTAGE (µV)
101520253035404550
Figure 4. Input Offset Voltage Distribution
25
20
05564-011
05564-016
OFFSET VOLTAGE (µV)
NUMBER OF AMPLIFIERS
150
100
–50
–100
–150
–200
120
100
160
140
120
50
0
80
60
40
20
0
–40 25 125
TEMPERATURE (°C)
Figure 6. Offset Voltage vs. Temperature
VS = ±15V
T
= 25°C
A
–0.65
–0.55
–0.45
–0.35
–0.25
–0.15
–0.05
IB (nA)
0.05
Figure 7. Input Bias Current, V
VS = ±5V
= 25°C
T
A
0.15
0.25
= ±15 V
S
05564-005
0.35
0.45
0.55
0.65
05564-006
NUMBER OF AMPL IFIERS
15
10
5
0
0
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
0.55
TCVOS (µV/°C)
Figure 5. T
CVOS
0.60
0.65
0.70
0.75
0.80
1.00
0.85
0.90
0.95
05564-014
100
80
60
NUMBER OF AMPLIFIERS
40
20
0
0.05
0.15
0.25
0.35
0.45
0.55
–0.65
–0.55
–0.45
–0.35
–0.25
Figure 8. Input Bias Current, V
–0.15
–0.05
IB (nA)
= ±5 V
S
0.65
05564-008
Rev. A | Page 6 of 12
Page 7
AD8675
5
4
3
2
1
0
(nA)
B
I
–1
VS= ±5V
VS= ±15V
–2
–3
–4
–5
–40 –20 0 20 40 60 80 100 120
TEMPERATURE (°C)
Figure 9. Input Bias Current vs. Temperature
3.0
2.5
2.0
1.5
1.0
SUPPLY CURRENT (mA)
0.5
0
5 101520253035
SUPPLY VOLTAGE (V)
Figure 10. Supply Current vs. Total Supply Voltage
3.5
= 35pF
= 55.2
100M
180
120
60
0
–60
–120
–180
PHASE MARGIN (Degrees)
05564-018
120
100
GAIN (dB)
–20
–40
–60
–80
–100
–120
05564-007
GAIN
80
60
PHASE
40
20
0
100
10k1k 100k 10M1M
FREQUENCY (Hz)
RL = 2kΩ
C
L
θ
M
Figure 12. Gain and Phase vs. Frequency
60
50
40
G = 100
30
20
G = 10
10
0
–10
CLOSED-LOOP GAIN (dB)
G = 1
–20
–30
–40
1k 10k 100k
05564-009
FREQUENCY (Hz)
1M 10M 100M
05564-030
Figure 13. Closed-Loop Gain vs. Frequency
70
3.0
VS= ±15V
2.5
2.0
(mA)
SY
I
1.5
VS= ±5V
1.0
0.5
0
–40 –20 0 20 40 60 80 100 120
TEMPERATURE (°C)
Figure 11. Supply Current vs. Temperature
05564-019
Rev. A | Page 7 of 12
60
50
40
(Ω)
OUT
Z
30
AVO= 100
AVO= 10
20
AVO= 1
10
0
1k 10k 100k 1M 10M 100M
FREQUENCY (Hz)
Figure 14. Z
vs. Frequency
OUT
05564-015
Page 8
AD8675
15
10
5
0
VOLTAGE (V)
–5
–10
–15
TIME (10µs/DIV)
Figure 15. Large Signal Transient Response, V
4
3
2
1
0
VOLTAGE (V)
–1
–2
–3
–4
TIME (10µs/DIV)
Figure 16. Large Signal Transient Response, V
70
AV = +1
= 100mV p-p
V
IN
60
50
40
+OS
30
OVERSHOOT (%)
–OS
20
10
0
1 10 100 1k 10k 100k
CAPACITANCE (pF)
Figure 17. Small Signal Overshoot vs. Load Capacitance
= ±15 V
SY
VIN = ±3.5V
R
A
= ±5 V
SY
VIN = ±11V
R
= 2kΩ
L
A
= +1
V
= 2kΩ
L
= +1
V
0.1
V
V
IN
OUT
TIME (µs)
VIN = 200mV p-p
A
= –100
VO
R
= 10kΩ
L
0
–0.1
–0.2
–0.3
–0.4
INPUT VOLTAGE (V)
–0.5
–0.6
–0.7
–4 1 6 11 16 21 26 31 36
05564-020
50
40
30
20
10
–0
–10
–20
–30
OUTPUT VOLTAGE (V)
05564-004
Figure 18. Positive Overvoltage Recovery
0.3
0.2
0.1
0
–0.1
–0.2
INPUT VOLTAGE (V)
–0.3
–0.4
–0.5
–4 1 6 11 16 21 26 31
05564-028
V
V
OUT
IN
TIME (µs)
VIN = 200mV p-p
A
= –100
VO
R
= 10kΩ
L
50
40
30
20
10
0
OUTPUT VOLTAGE (V)
–10
–20
–30
36
05564-003
Figure 19. Negative Overvoltage Recovery
180
160
140
120
100
80
CMRR (dB)
60
40
20
0
–20
10 100 10k1k 100k 10M1M 100M
05564-012
FREQUENCY (Hz)
05564-029
Figure 20. CMRR vs. Frequency
Rev. A | Page 8 of 12
Page 9
AD8675
–
160
140
1000
TA = 25°C
120
100
80
60
PSRR (dB)
40
20
0
–20
10 100 10k1k 100k 10M1M 100M
+PSRR
FREQUENCY (Hz)
–PSRR
Figure 21. PSRR vs. Frequency
148
147
146
145
144
PSRR (dB)
143
SOURCE
100
(mV)
OUT
– V
S
V
10
1
0.001 0.01 0.1 1 10 100
05564-022
LOAD CURRENT (mA)
SINK
05564-010
Figure 24. Output Saturation Voltage vs. Output Current
+SWING (V)
14.86
14.84
14.82
14.80
14.78
14.76
V
OH
VS = ±15V
R
= 2kΩ
L
142
141
140
–40 –20 0 20 40 60 80 100 120
TEMPERATURE (° C)
Figure 22. Power Supply Rejection Ratio vs. Temperature
0.06
0.04
0.02
0
NOISE (µV)
–0.02
–0.04
–0.06
012 4376589
TIME (s)
Figure 23. Voltage Noise (0.1 Hz to 10 Hz)
05564-023
10
05564-021
14.74
14.72
14.70
–40 –20 0 20 40 60 80 100 120
TEMPERATURE (°C)
Figure 25. Swing vs. Temperature, V
14.70
–14.75
–14.80
–14.85
–SWING (V)
–14.90
–14.95
–15.00
–40–200 20406080100120
V
OL
TEMPERATURE (°C)
Figure 26. Swing vs. Temperature, V
OH
OL
VS = ±15V
R
L
=2kΩ
05564-032
05564-033
Rev. A | Page 9 of 12
Page 10
AD8675
Ω
2
–
INPUT OUTPUT
3
+
1
8
AD8675
4
V–
100k
7
6
V
TRIM RANGE IS
OS
TYPICALLY ±3.5mV
V+
5564-031
Figure 27. Optional Offset Nulling Circuit
Rev. A | Page 10 of 12
Page 11
AD8675
OUTLINE DIMENSIONS
5.00 (0.1968)
4.80 (0.1890)
4.00 (0.1574)
3.80 (0.1497)
0.25 (0.0098)
0.10 (0.0040)
COPLANARI TY
0.10
CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF MILLIM ETER EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIG N.
85
1
1.27 (0.0500)
SEATING
PLANE
COMPLIANT TO JEDEC STANDARDS MS-012-AA
BSC
6.20 (0.2441)
5.80 (0.2284)
4
1.75 (0.0688)
1.35 (0.0532)
0.51 (0.0201)
0.31 (0.0122)
8°
0°
0.25 (0.0098)
0.17 (0.0067)
0.50 (0.0196)
0.25 (0.0099)
1.27 (0.0500)
0.40 (0.0157)
45°
0.95
0.85
0.75
0.15
0.00
012407-A
COPLANARITY
Figure 28. 8-Lead Standard Small Outline Package [SOIC_N]
Narrow Body (R-8)
Dimensions shown in millimeters and (inches)
ORDERING GUIDE
Model Temperature Range Package Description Package Option Branding
AD8675ARMZ-R2
AD8675ARMZ-REEL
AD8675ARZ
AD8675ARZ-REEL
AD8675ARZ-REEL7
1
Z = RoHS Compliant Part.
1
−40°C to +125°C 8-Lead Mini Small Outline Package [MSOP] RM-8 A08
1
1
−40°C to +125°C 8-Lead Mini Small Outline Package [MSOP] RM-8 A08
−40°C to +125°C 8-Lead Standard Small Outline Package [SOIC_N] R-8
1
−40°C to +125°C 8-Lead Standard Small Outline Package [SOIC_N] R-8
1
−40°C to +125°C 8-Lead Standard Small Outline Package [SOIC_N] R-8
3.20
3.00
2.80
8
5
4
SEATING
PLANE
5.15
4.90
4.65
1.10 MAX
0.23
0.08
8°
0°
3.20
3.00
1
2.80
PIN 1
0.65 BSC
0.38
0.22
0.10
COMPLIANT TO JEDEC STANDARDS MO-187-AA
Figure 29. 8-Lead Mini Small Outline Package [MSOP]
(RM-8)
Dimensions shown in millimeters
0.80
0.60
0.40
Rev. A | Page 11 of 12
Page 12
AD8675
NOTES
©2005-2007 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D05564-0-4/07(A)
Rev. A | Page 12 of 12
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