High Temperature, Low Power
Operational Amplifier
AD8634
Data Sheet
PIN CONFIGURATION
Extreme high temperature operation
−40°C to +210°C, FLATPACK package
−40°C to +175°C, SOIC package
Rail-to-rail output
Low power: 1.3 mA maximum
Gain bandwidth product: 9.7 MHz typical at AV = 100
Low offset voltage: 250 μV maximum
Unity-gain stable
High slew rate: 5.0 V/μs typical at 210°C
Low noise: 4.2 nV/√Hz typical at 1 kHz and 210°C
OUT A 1
8
V+
–IN A 2
7
OUT B
+IN A 3
6
–IN B
V– 4
5
+IN B
AD8634
TOP VIEW
(Not to Scale)
11524-001
FEATURES
Figure 1. SOIC and FLATPACK Pinout
APPLICATIONS
Downhole drilling and instrumentation
Avionics
Heavy industrial
High temperature environments
GENERAL DESCRIPTION
The AD8634 is a precision, 9.7 MHz bandwidth, dual amplifier
that features rail-to-rail outputs. The AD8634 is guaranteed to
operate from 3 V to 30 V (or from ±1.5 V to ±15 V) and at very
high temperatures.
The AD8634 is well suited for applications that require both
ac and dc precision performance. The combination of wide
bandwidth, low noise, and precision makes the AD8634 useful
in a wide variety of applications, including filters and interfacing
with a variety of sensors.
Rev. A
This dual-channel op amp is offered in an 8-lead SOIC package
with an operating temperature range of −40°C to +175°C. It is
also available in an 8-lead ceramic flat package (FLATPACK)
with an operating temperature range of −40°C to +210°C. Both
packages are designed for robustness at extreme temperatures and
are qualified for up to 1000 hours of operation at the maximum
temperature rating.
The AD8634 is a member of a growing series of high temperature
qualified products offered by Analog Devices, Inc. For a complete
selection table of available high temperature products, see the
high temperature product list and qualification data available at
http://www.analog.com/hightemp.
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Tel: 781.329.4700 ©2013–2014 Analog Devices, Inc. All rights reserved.
Technical Support
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AD8634
Data Sheet
TABLE OF CONTENTS
Features .............................................................................................. 1
Absolute Maximum Ratings ............................................................5
Applications ....................................................................................... 1
Predicted Lifetime vs. Operating Temperature .........................5
General Description ......................................................................... 1
Thermal Resistance .......................................................................5
Pin Configuration ............................................................................. 1
ESD Caution...................................................................................5
Revision History ............................................................................... 2
Typical Performance Characteristics ..............................................6
Specifications..................................................................................... 3
Applications Information .............................................................. 10
Electrical Characteristics, VSY = ±15.0 V................................... 3
Input Protection ......................................................................... 10
Electrical Characteristics, VSY = 3.0 V ....................................... 4
Outline Dimensions ....................................................................... 11
Ordering Guide .......................................................................... 11
REVISION HISTORY
7/14—Rev. 0 to Rev. A
Changes to Unity-Gain Crossover Parameter, Table 1 and
−3 dB Closed-Loop Bandwidth Parameter, Table 1 ..................... 3
Changes to Unity-Gain Crossover Parameter, Table 2 and
−3 dB Closed-Loop Bandwidth Parameter, Table 2 ..................... 4
7/13—Revision 0: Initial Version
Rev. A | Page 2 of 12
Data Sheet
AD8634
SPECIFICATIONS
ELECTRICAL CHARACTERISTICS, VSY = ±15.0 V
VSY = ±15.0 V, VCM = 0 V, TMIN ≤ TA ≤ TMAX, unless otherwise noted.
Table 1.
Parameter
INPUT CHARACTERISTICS
Offset Voltage
Offset Voltage Drift
Offset Voltage Matching
Input Bias Current
Input Offset Current
Input Voltage Range
Common-Mode Rejection
Ratio
Large Signal Voltage Gain
Input Impedance
Differential
Common-Mode
OUTPUT CHARACTERISTICS
Output Voltage High
Output Voltage Low
Short-Circuit Current
POWER SUPPLY
Power Supply Rejection
Ratio
Supply Current per
Amplifier
DYNAMIC PERFORMANCE
Slew Rate
Gain Bandwidth Product
Unity-Gain Crossover
−3 dB Closed-Loop
Bandwidth
Phase Margin
NOISE PERFORMANCE
Voltage Noise
Voltage Noise Density
Current Noise Density
Symbol
SOIC Package
−40°C ≤ TA ≤ +175°C
Min
Typ
Max
Test Conditions/
Comments
VOS
ΔVOS/ΔT
250
AVO
250
VCM = −14.0 V to +14.0 V
−13.5 V ≤ VOUT ≤ +13.5 V,
RL = 2 kΩ
−200
−40
120
−14.5
100
115
112
100
108
dB
53||1.1
1.1||2.5
kΩ||pF
GΩ||pF
14.90
14.5
14.75
−14.95
−14.75
V
V
V
V
V
V
mA
−200
−45
−14.7
105
104
0.35
150
+200
30
+14.7
53||1.1
1.1||2.5
VOH
14.8
14.0
14.60
ISC
RL = 10 kΩ to VCM
RL = 2 kΩ to VCM
RL = 2 kΩ to VCM, TA = TMAX
RL = 10 kΩ to VCM
RL = 2 kΩ to VCM
RL = 2 kΩ to VCM, TA = TMAX
VOUT = 0 V, TA = TMAX
PSRR
VSY = ±2 V to ±18 V
105
ISY
IOUT = 0 mA, TA = TMAX
SR
GBP
RL = 2 kΩ
VIN = 5 mV p-p, RL = 10 kΩ,
AV = 100
VIN = 5 mV p-p, RL = 10 kΩ,
AV = 1
VIN = 5 mV p-p, AV = 1
VOL
UGC
−3 dB
14.8
14.0
14.60
−14.8
−14.70
−14.70
0.1 Hz to 10 Hz
f = 1 kHz
Rev. A | Page 3 of 12
4.9
9.7
150
+200
30
+14.5
−14.8
−14.65
−14.65
+105/−18
115
1.0
ΦM
en p-p
en
in
14.90
14.5
14.75
−14.95
−14.8
+100/−20
3.6
Unit
μV
μV/°C
μV
nA
nA
V
dB
0.35
TA = TMAX
IB
IOS
VIN
CMRR
FLATPACK Package
−40°C ≤ TA ≤ +210°C
Min
Typ
Max
103
1.2
113
1.1
3.6
dB
1.3
mA
5.0
9.7
V/µs
MHz
7.0
7.0
MHz
11.0
11.0
MHz
84
82
Degrees
0.13
4.2
0.6
0.13
4.2
0.6
µV p-p
nV/√Hz
pA/√Hz
AD8634
Data Sheet
ELECTRICAL CHARACTERISTICS, VSY = 3.0 V
VSY = 3.0 V, VCM = 1.5 V, VOUT = 1.5 V, TMIN ≤ TA ≤ TMAX, unless otherwise noted.
Table 2.
Parameter
INPUT CHARACTERISTICS
Offset Voltage
Offset Voltage Drift
Offset Voltage Matching
Input Bias Current
Input Offset Current
Input Voltage Range
Common-Mode Rejection
Ratio
Large Signal Voltage Gain
Input Impedance
Differential
Common-Mode
OUTPUT CHARACTERISTICS
Output Voltage High
Output Voltage Low
Short-Circuit Current
POWER SUPPLY
Power Supply Rejection
Ratio
Supply Current per
Amplifier
DYNAMIC PERFORMANCE
Slew Rate
Gain Bandwidth Product
Unity-Gain Crossover
−3 dB Closed-Loop
Bandwidth
Phase Margin
NOISE PERFORMANCE
Voltage Noise
Voltage Noise Density
Current Noise Density
Symbol
SOIC Package
−40°C ≤ TA ≤ +175°C
Min
Typ
Max
Test Conditions/
Comments
VOS
ΔVOS/ΔT
250
AVO
250
VCM = 0.3 V to 2.7 V
0.5 V ≤ VOUT ≤ 2.5 V,
RL = 2 kΩ
−200
−40
65
0.5
55
60
112
100
108
dB
53||1.1
2.8||2.5
kΩ||pF
GΩ||pF
2.90
2.5
2.75
50
250
V
V
V
mV
mV
mV
mA
−200
−45
0.3
60
104
0.35
150
+200
30
2.7
53||1.1
2.8||2.5
VOH
2.8
2.0
2.60
ISC
RL = 10 kΩ to VCM
RL = 2 kΩ to VCM
RL = 2 kΩ to VCM, TA = TMAX
RL = 10 kΩ to VCM
RL = 2 kΩ to VCM
RL = 2 kΩ to VCM, TA = TMAX
VOUT = 0 V, TA = TMAX
PSRR
VSY = ±1.25 V to ±1.75 V
97
ISY
IOUT = 0 mA, TA = TMAX
SR
GBP
RL = 2 kΩ
VIN = 5 mV p-p, RL = 10 kΩ,
AV = 100
VIN = 5 mV p-p, RL = 10 kΩ,
AV = 1
VIN = 5 mV p-p, AV = 1
VOL
UGC
−3 dB
2.8
2.0
2.60
200
300
300
0.1 Hz to 10 Hz
f = 1 kHz
Rev. A | Page 4 of 12
4.9
9.7
150
+200
30
2.5
200
350
350
+70/−11
102
0.9
ΦM
en p-p
en
in
2.90
2.5
2.75
50
200
+65/−13
3.5
Unit
μV
μV/°C
μV
nA
nA
V
dB
0.35
TA = TMAX
IB
IOS
VIN
CMRR
FLATPACK Package
−40°C ≤ TA ≤ +210°C
Min
Typ
Max
95
1.1
100
1.0
3.5
dB
1.2
mA
5.0
9.7
V/µs
MHz
7.0
7.0
MHz
11.0
11.0
MHz
84
82
Degrees
0.13
4.2
0.6
0.13
4.2
0.6
µV p-p
nV/√Hz
pA/√Hz
Data Sheet
AD8634
ABSOLUTE MAXIMUM RATINGS
100k
1
Rating
±18 V
V− ≤ VIN ≤ V+
±0.6 V
Indefinite
−65°C to +150°C
PREDICTED LIFETIME (Hours)
Parameter
Supply Voltage
Input Voltage
Differential Input Voltage1
Output Short-Circuit Duration to GND
Storage Temperature Range
Operating Temperature Range
SOIC Package
FLATPACK Package
Junction Temperature
SOIC Package
FLATPACK Package
Lead Temperature (Soldering 60 sec)
−40°C to +175°C
−40°C to +210°C
200°C
245°C
300°C
10k
1k
100
10
1
120
130
140
150
160
170
180
190
200
210
OPERATING TEMPERATURE (°C)
Figure 2. Predicted Lifetime vs. Operating Temperature
For differential input voltages greater than 0.6 V, limit the input current to
less than 5 mA to prevent degradation or destruction of the input devices
(see the Input Protection section).
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 the device soldered on a 4-layer JEDEC
standard printed circuit board (PCB) with zero airflow.
Table 4. Thermal Resistance
Package Type
8-Lead SOIC_N
8-Lead FLATPACK
ESD CAUTION
PREDICTED LIFETIME vs. OPERATING
TEMPERATURE
Comprehensive reliability testing is performed on all Analog
Devices high temperature products, including the AD8634.
Product lifetimes at extended operating temperature are obtained
using high temperature operating life (HTOL). Lifetimes are
predicted from the Arrhenius equation, taking into account
assumptions about potential design and manufacturing failure
mechanisms. HTOL is performed in accordance with JEDEC
JESD22-A108. A minimum of three wafer fab and assembly
lots are processed through HTOL at the maximum operating
temperature.
Rev. A | Page 5 of 12
θJA
121
100
θJC
43
15
Unit
°C/W
°C/W
11524-126
Table 3.
AD8634
Data Sheet
TYPICAL PERFORMANCE CHARACTERISTICS
60
80
70
NUMBER OF AMPLIFIERS
50
40
30
20
30
20
10
10
–60
–40
–20
0
20
40
60
80
100
0
VOS (µV)
–100
–95
–90
–85
–80
–75
–70
–65
–60
–55
–50
–45
–40
–35
–30
–25
–20
–15
–10
–5
0
–100 –80
11524-120
0
40
IB (nA)
Figure 3. Offset Voltage Distribution, SOIC Package,
VSY = ±15.0 V, TA = 175°C
11524-105
NUMBER OF AMPLIFIERS
50
60
Figure 6. Input Bias Current Distribution, SOIC Package,
VSY = ±15.0 V, TA = 175°C
25
10
9
8
NUMBER OF AMPLIFIERS
NUMBER OF AMPLIFIERS
20
15
10
5
7
6
5
4
3
2
1
TCVOS (µV/°C)
0
IOS (nA)
Figure 7. Input Offset Current Distribution, SOIC Package,
VSY = ±15.0 V, TA = 175°C
Figure 4. TCVOS Distribution, SOIC Package, VSY = ±15.0 V
0
40
20
11524-106
0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 0.55 0.60
–2.6
–2.4
–2.2
–2.0
–1.8
–1.6
–1.4
–1.2
–1.0
–0.8
–0.6
–0.4
–0.2
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
0
11524-121
0
VSY = ±15V
VCM = 0V
VSY = ±15V
VCM = 0V
–10
INPUT BIAS CURRENT (nA)
–20
–40
–60
–30
–40
–50
–60
IB+
IB–
–70
–80
–80
–50
0
50
100
150
TEMPERATURE (°C)
200
250
–100
–100
–50
0
50
100
150
TEMPERATURE (°C)
200
Figure 8. Typical Input Bias Current vs. Temperature
Figure 5. Typical Offset Voltage vs. Temperature
Rev. A | Page 6 of 12
250
11524-107
–90
–100
–100
11524-104
OFFSET VOLTAGE (µV)
–20
0
Data Sheet
AD8634
400
0
–20
200
100
0
–100
–200
–60
–80
–100
–40°C
+25°C
+175°C
+210°C
–120
–300
0
2
4
6
8
10 12 14 16
COMMON-MODE VOLTAGE (V)
–140
–16 –14 –12 –10 –8 –6 –4 –2
11524-108
–400
–16 –14 –12 –10 –8 –6 –4 –2
Figure 9. Offset Voltage vs. Common-Mode Voltage and Temperature,
VSY = ±15.0 V
0
2
4
6
8
10 12 14 16
COMMON-MODE VOLTAGE (V)
Figure 12. Input Bias Current vs. Common-Mode Voltage and Temperature,
VSY = ±15.0 V
100
100
–40°C
+175°C
+210°C
10
VOH – VDD (V)
10
VOL – VSS (V)
–40
11524-111
–40°C
+25°C
+210°C
INPUT BIAS CURRENT (nA)
OFFSET VOLTAGE (µV)
300
1
100m
1
–40°C
+25°C
+210°C
100m
1
10
100
ILOAD (mA)
10m
11524-109
1m
0.1
Figure 10. Negative Dropout Voltage vs. Load Current and Temperature
1
10
100
1000
ILOAD (mA)
11524-112
10m
Figure 13. Positive Dropout Voltage vs. Load Current and Temperature
120
120
VSY = ±15V
TA = 210°C
VSY = ±15V
TA = 210°C
100
100
80
PSRR (dB)
60
60
40
40
20
20
1k
10k
100k
FREQUENCY (Hz)
1M
10M
–20
100
+PSRR
–PSRR
1k
10k
100k
1M
FREQUENCY (Hz)
Figure 11. CMRR vs. Frequency, TA = 210°C
Figure 14. PSRR vs. Frequency
Rev. A | Page 7 of 12
10M
100M
11524-018
0
100
0
11524-110
CMRR (dB)
80
AD8634
Data Sheet
180
20
45
0
0
–20
GAIN
PHASE MARGIN
10k
100k
1M
–90
100M
10M
1000
500
–45
–40
1k
1500
0
FREQUENCY (Hz)
5
0
10
Figure 15. Gain and Phase Margin vs. Frequency, TA = 210°C
INPUT
25
20
30
Δ: 1.61V
@: –710mV
Δ: 280ns
@: –140ns
OUTPUT
INPUT
CH1 AMPL
2.93V
CH2 500mV
A CH1
CH1 AMPL
2.91V
11524-021
CH1 500mV
0V
CH1 500mV
Figure 16. Large Signal Positive Edge Response, VSY = ±15.0 V,
TA = 175°C
INPUT
CH2 500mV
A CH1
0V
Figure 19. Large Signal Positive Edge Response, VSY = ±15.0 V,
TA = 210°C
Δ: 1.69V
@: –750mV
Δ: 320ns
@: 140ns
OUTPUT
Δ: 1.67V
@: 830mV
Δ: 280ns
@: –140ns
OUTPUT
INPUT
CH2 500mV
A CH1
0V
CH1 AMPL
2.91V
11524-023
CH1 AMPL
2.92V
CH1 500mV
35
Figure 18. Supply Current vs. Supply Voltage and Temperature
Δ: 1.85V
@: 920mV
Δ: 320ns
@: 140ns
OUTPUT
15
SUPPLY VOLTAGE (V)
11524-117
90
2000
11524-020
40
–40°C
+25°C
+175°C
+210°C
CH1 500mV
Figure 17. Large Signal Negative Edge Response, VSY = ±15.0 V,
TA = 175°C
CH2 500mV
A CH1
0V
Figure 20. Large Signal Negative Edge Response, VSY = ±15.0 V,
TA = 210°C
Rev. A | Page 8 of 12
11524-022
135
SUPPLY CURRENT (µA)
60
2500
PHASE MARGIN (Degrees)
VSY = ±15V
RL = 10kΩ
11524-114
GAIN (dB)
80
Data Sheet
AD8634
1000
VOLTAGE NOISE DENSITY (nV/√Hz)
VSY = ±15V
100
+25°C
+210°C
1
10
1k
100
FREQUENCY (Hz)
10k
11524-125
10
Figure 21. Voltage Noise Density vs. Frequency
Rev. A | Page 9 of 12
AD8634
Data Sheet
APPLICATIONS INFORMATION
Figure 22 illustrates a typical noninverting configuration for
an overvoltage-protected amplifier where the series resistance,
RS, is chosen such that
Figure 23 illustrates a typical application circuit that uses the
AD8634 and other Analog Devices high temperature products.
INPUT PROTECTION
RS = (VIN (MAX) − VSUPPLY)/5 mA
As with any semiconductor device, if the input voltages applied
to the AD8634 exceed either supply voltage, the input overvoltage
I-to-V characteristic of the device must be considered. When
an overvoltage condition occurs, the amplifier can be damaged,
depending on the magnitude of the applied voltage and the
magnitude of the fault current.
R2
1/2
VOUT
AD8634
VIN
The protection diodes between the input and supply pins conduct
when the input common-mode voltage exceeds either supply pin
by a diode drop. This diode drop varies with temperature and is in
the range of 0.3 V to 0.8 V. The AD8634 has no internal currentlimiting resistors; therefore, fault currents can quickly rise to
damaging levels.
11524-075
RS
Figure 22. Resistance in Series with Inputs
Limits Overvoltage Currents to Safe Values
For example, a 1 kΩ resistor protects the AD8634 against
input signals up to 5 V above and below the supplies. Note
that the thermal noise of a 1 kΩ resistor at room temperature
is 4 nV/√Hz, which is close to the voltage noise of the AD8634.
This input current is not inherently damaging to the device,
provided that it is limited to 5 mA or less. If a fault condition
causes more than 5 mA to flow, an external series resistor
should be added at the expense of additional thermal noise.
For configurations where both inputs are used, add a series
resistor at each input to protect the inputs against damage. To
ensure optimum dc and ac performance, it is recommended
that source impedance levels be balanced.
VCC
VCC
+5V
+5V
U1
ADR225
C2
0.1µF
GND
+ C3
1µF
C4
0.1µF
VCC
AD8634
+5V
R3
2.5kΩ
U3
AD8229
–5V
VEE
R1
2.5kΩ
SIGNAL OUT
RTD
–5V
VEE
Figure 23. Typical High Temperature RTD Signal Conditioning Circuit
Rev. A | Page 10 of 12
11524-076
OUTPUT
+ C1
10µF
U2A
R2
2.5kΩ
VS
Data Sheet
AD8634
OUTLINE DIMENSIONS
5.00 (0.1968)
4.80 (0.1890)
1
5
4
1.27 (0.0500)
BSC
0.25 (0.0098)
0.10 (0.0040)
COPLANARITY
0.10
SEATING
PLANE
6.20 (0.2441)
5.80 (0.2284)
1.75 (0.0688)
1.35 (0.0532)
0.51 (0.0201)
0.31 (0.0122)
0.50 (0.0196)
0.25 (0.0099)
45°
8°
0°
0.25 (0.0098)
0.17 (0.0067)
1.27 (0.0500)
0.40 (0.0157)
COMPLIANT TO JEDEC STANDARDS MS-012-AA
CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN.
012407-A
8
4.00 (0.1574)
3.80 (0.1497)
Figure 24. 8-Lead Standard Small Outline Package [SOIC_N]
Narrow Body
(R-8)
Dimensions shown in millimeters and (inches)
1.00
0.260
0.255 SQ
0.250
0.195
0.190 SQ
0.185
1
0.155
0.150
0.145
8
4
0.012 R
TYP
0.006
0.005
0.004
0.035
TYP
0.019
0.017
0.015
5
TOP VIEW
0.05 TYP
IDEX
MARK
0.091
0.083
0.075
END VIEW
0.026 MIN
0.054
0.044
0.034
BOTTOM VIEW
0.024
0.007
MIN
SIDE VIEW
03-26-2013-A
0.053
0.050
0.047
0.175
Figure 25. 8-Lead Ceramic Flat Package [FLATPACK]
(F-8-2)
Dimensions shown in inches
ORDERING GUIDE
Model1
AD8634HRZN
AD8634HFZ
1
Temperature Range
−40°C to +175°C
−40°C to +210°C
Package Description
8-Lead Standard Small Outline Package [SOIC_N]
8-Lead Ceramic Flat Package [FLATPACK]
Z = RoHS Compliant Part.
Rev. A | Page 11 of 12
Package Option
R-8
F-8-2
AD8634
Data Sheet
NOTES
©2013–2014 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D11524-0-7/14(A)
Rev. A | Page 12 of 12