AD629 [AAVID]
Very Low Distortion, Precision Difference Amplifier; 非常低的失真，精密差分放大器
| 型号： | AD629 |
| 厂家： | 
AAVID THERMALLOY, LLC |
| 描述： | Very Low Distortion, Precision Difference Amplifier |
| 文件： | 总16页 (文件大小：375K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
Very Low Distortion,
Precision Difference Amplifier
AD8274
FUNCTIONAL BLOCK DIAGRAM
FEATURES
+V
S
Very low distortion
7
0.00025% THD + N (20 kHz)
0.0015% THD + N (100 kHz)
Drives 600 Ω loads
12kΩ
12kΩ
6kΩ
6kΩ
2
5
6
Excellent gain accuracy
0.03% maximum gain error
2 ppm/°C maximum gain drift
Gain of ½ or 2
3
1
AC specifications
20 V/μs minimum slew rate
800 ns to 0.01% settling time
High accuracy dc performance
83 dB minimum CMRR
4
–V
S
Figure 1.
700 μV maximum offset voltage
8-lead SOIC and MSOP packages
Supply current: 2.6 mA maximum
Supply range: 2.5 V to 18 V
Table 1. Difference Amplifiers by Category
Low
Distortion
High
Voltage
Single-Supply
Unidirectional
Single-Supply
Bidirectional
APPLICATIONS
ADC driver
AD8270
AD8273
AD8274
AMP03
AD628
AD629
AD8202
AD8203
AD8205
AD8206
AD8216
High performance audio
Instrumentation amplifier building blocks
Level translators
Automatic test equipment
Sine/cosine encoders
GENERAL DESCRIPTION
The AD8274 is a difference amplifier that delivers excellent ac
and dc performance. Built on Analog Devices, Inc., proprietary
iPolar® process and laser-trimmed resistors, AD8274 achieves a
breakthrough in distortion vs. current consumption and has
excellent gain drift, gain accuracy, and CMRR.
With no external components, the AD8274 can be configured
as a G = ½ or G = 2 difference amplifier. For single-ended
applications that need high gain stability or low distortion
performance, the AD8274 can also be configured for several
gains ranging from −2 to +3.
Distortion in the audio band is an extremely low 0.00025%
(112 dB) at a gain of ½ and 0.00035% (109 dB) at a gain of 2
while driving a 600 Ω load
The excellent distortion and dc performance of the AD8274,
along with its high slew rate and bandwidth, make it an excellent
ADC driver. Because of the part’s high output drive, it also
makes a very good cable driver.
With supply voltages up to 18 V (+36 V single supply), the
AD8274 is well suited for measuring large industrial signals.
Additionally, the part’s resistor divider architecture allows it to
measure voltages beyond the supplies.
The AD8274 only requires 2.6 mA maximum supply current. It
is specified over the industrial temperature range of −40°C to
+85°C and is fully RoHS compliant. For the dual version, see the
AD8273 data sheet.
Rev. C
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 registeredtrademarks arethe 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 ©2008–2011 Analog Devices, Inc. All rights reserved.
AD8274
TABLE OF CONTENTS
Features .............................................................................................. 1
Pin Configurations and Function Description..............................5
Typical Performance Characteristics ..............................................6
Theory of Operation ...................................................................... 12
Circuit Information.................................................................... 12
Driving the AD8274................................................................... 12
Power Supplies............................................................................ 12
Input Voltage Range................................................................... 12
Configurations............................................................................ 13
Driving Cabling.......................................................................... 14
Outline Dimensions....................................................................... 15
Ordering Guide .......................................................................... 15
Applications....................................................................................... 1
Functional Block Diagram .............................................................. 1
General Description......................................................................... 1
Revision History ............................................................................... 2
Specifications..................................................................................... 3
Absolute Maximum Ratings............................................................ 4
Thermal Resistance ...................................................................... 4
Maximum Power Dissipation ..................................................... 4
Short-Circuit Current .................................................................. 4
ESD Caution.................................................................................. 4
REVISION HISTORY
8/11—Rev. B to Rev. C
Changes to Input Voltage Range Parameter, Table 2 ................... 3
1/11—Rev. A to Rev. B
Changes to Impedance/Differential Parameter, Table 2.............. 3
Changes to Figure 17........................................................................ 8
Updated Outline Dimensions....................................................... 15
12/08—Rev. 0 to Rev. A
Changes to Figure 8 and Figure 10................................................. 6
7/08—Revision 0: Initial Version
Rev. C | Page 2 of 16
AD8274
SPECIFICATIONS
VS = 15 V, VREF = 0 V, TA = 25°C, RL = 2 kꢀ, unless otherwise noted.
Table 2.
G = ½
Typ
G = 2
Typ
Parameter
Conditions
Min
Max
Min
Max
Unit
DYNAMIC PERFORMANCE
Bandwidth
Slew Rate
20
10
MHz
V/μs
ns
20
20
Settling Time to 0.1%
10 V step on output,
CL = 100 pF
10 V step on output,
CL = 100 pF
650
725
750
800
675
750
775
825
Settling Time to 0.01%
ns
NOISE/DISTORTION1
THD + Noise
f = 1 kHz,
0.00025
0.00035
%
VOUT = 10 V p-p,
600 Ω load
20 kHz BW
Noise Floor, RTO2
−106
3.5
−100
7
dBu
μV rms
Output Voltage Noise
(Referred to Output)
f = 20 Hz to 20 kHz
f = 1 kHz
26
52
nV/√Hz
GAIN
Gain Error
Gain Drift
Gain Nonlinearity
0.03
2
0.03
2
%
−40°C to +85°C
VOUT = 10 V p-p,
600 Ω load
0.5
2
0.5
2
ppm/°C
ppm
INPUT CHARACTERISTICS
Offset3
vs. Temperature
vs. Power Supply
Common-Mode Rejection VCM
Referred to output
−40°C to +85°C
VS = 2.5 V to 18 V
150
3
700
5
300
6
1100
10
μV
μV/°C
μV/V
dB
=
40 V,
77
86
83
92
Ratio
RS = 0 Ω,
referred to input
Input Voltage Range4
Impedance5
Differential
Common Mode6
3(−VS + 1.5)
3(+VS − 1.5) 1.5(−VS + 1.5)
1.5(+VS – 1.5)
+VS − 1.5
V
VCM = 0 V
36
9
9
9
kΩ
kΩ
OUTPUT CHARACTERISTICS
Output Swing
−VS + 1.5
+VS − 1.5
−VS + 1.5
V
Short-Circuit Current Limit
Sourcing
Sinking
90
60
200
90
60
1200
mA
mA
pF
Capacitive Load Drive
POWER SUPPLY
Supply Current (per
Amplifier)
2.3
2.6
2.3
2.6
mA
°C
TEMPERATURE RANGE
Specified Performance
−40
+85
−40
+85
1 Includes amplifier voltage and current noise, as well as noise of internal resistors.
2 dBu = 20 log(V rms/0.7746).
3 Includes input bias and offset current errors.
4 May also be limited by absolute maximum input voltage or by the output swing. See the Absolute Maximum Ratings section and Figure 8 through Figure 11 for details.
5 Internal resistors are trimmed to be ratio matched but to have 20% absolute accuracy.
6 Common mode is calculated by looking into both inputs. The common-mode impedance at only one input is 18 kΩ.
Rev. C | Page 3 of 16
AD8274
ABSOLUTE MAXIMUM RATINGS
MAXIMUM POWER DISSIPATION
Table 3.
The maximum safe power dissipation for the AD8274 is limited
by the associated rise in junction temperature (TJ) on the die. At
approximately 150°C, which is the glass transition temperature,
the properties of the plastic change. Even temporarily exceeding
this temperature limit may change the stresses that the package
exerts on the die, permanently shifting the parametric performance
of the amplifiers. Exceeding a temperature of 150°C for an
extended period may result in a loss of functionality.
2.0
Parameter
Rating
Supply Voltage
18 V
Maximum Voltage at Any Input Pin
Minimum Voltage at Any Input Pin
Storage Temperature Range
Specified Temperature Range
Package Glass Transition Temperature (TG)
−VS + 40 V
+VS – 40 V
−65°C to +150°C
−40°C to +85°C
150°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.
T
MAX = 150°C
J
1.6
1.2
0.8
0.4
0
SOIC
θ
= 121°C/W
JA
MSOP
= 135°C/W
θ
JA
THERMAL RESISTANCE
The θJA values in Table 4 assume a 4-layer JEDEC standard
board with zero airflow.
Table 4. Thermal Resistance
–50
–25
0
25
50
75
100
125
Package Type
8-Lead MSOP
8-Lead SOIC
θJA
Unit
°C/W
°C/W
AMBIENT TEMERATURE (°C)
135
121
Figure 2. Maximum Power Dissipation vs. Ambient Temperature
SHORT-CIRCUIT CURRENT
The AD8274 has built-in, short-circuit protection that limits the
output current (see Figure 16 for more information). While the
short-circuit condition itself does not damage the part, the heat
generated by the condition can cause the part to exceed its
maximum junction temperature, with corresponding negative
effects on reliability. Figure 2 and Figure 16, combined with
knowledge of the part’s supply voltages and ambient temperature,
can be used to determine whether a short circuit will cause the
part to exceed its maximum junction temperature.
ESD CAUTION
Rev. C | Page 4 of 16
AD8274
PIN CONFIGURATIONS AND FUNCTION DESCRIPTION
REF
–IN
1
2
3
4
8
7
6
5
NC
+V
REF
–IN
1
2
3
4
8
7
6
5
NC
+V
AD8274
AD8274
S
S
TOP VIEW
+IN
OUT
+IN
OUT
TOP VIEW
(Not to Scale)
(Not to Scale)
–V
S
SENSE
–V
S
SENSE
NC = NO CONNECT
NC = NO CONNECT
Figure 4. SOIC Pin Configuration
Figure 3. MSOP Pin Configuration
Table 5. Pin Function Descriptions
Pin No.
Mnemonic
Description
1
REF
6 kΩ Resistor to Noninverting Terminal of Op Amp. Used as reference pin in G = ½ configuration. Used as
positive input in G = 2 configuration.
2
3
−IN
+IN
12 kΩ Resistor to Inverting Terminal of Op Amp. Used as negative input in G = ½ configuration. Connect
to output in G = 2 configuration.
12 kΩ Resistor to Noninverting Terminal of Op Amp. Used as positive input in G = ½ configuration. Used
as reference pin in G = 2 configuration.
4
5
−VS
SENSE
Negative Supply.
6 kΩ Resistor to Inverting Terminal of Op Amp. Connect to output in G = ½ configuration. Used as
negative input in G = 2 configuration.
6
7
8
OUT
+VS
NC
Output.
Positive Supply.
No Connect.
Rev. C | Page 5 of 16
AD8274
TYPICAL PERFORMANCE CHARACTERISTICS
VS = 15 V, TA = 25°C, gain = ½, difference amplifier configuration, unless otherwise noted.
30
20
15
G = ½
0V, +25V
20
10
V
= ±15V
S
5
10
–13.5V, +11.5V
–13.5V, –11.5V
+13.5V, +11.5V
0
0
–5
–10
–15
–20
–25
–30
+13.5V, –11.5V
–10
–20
–30
REPRESENTATIVE SAMPLES
0V, –25V
0
–15
–10
–5
5
10
15
–50
–30
–10
10
30
50
70
90
110
130
OUTPUT VOLTAGE (V)
TEMPERATURE (°C)
Figure 5. CMR vs. Temperature, Normalized at 25°C, Gain = ½
Figure 8. Input Common-Mode Voltage vs. Output Voltage,
Gain = ½, 15 V Supplies
20
150
100
50
G = ½
–3.5V, +15.8V
15
V
= ±5V
S
+3.5V, +8.8V
10
5
V
= ±2.5V
S
–1.0V, +6.2V
–1.0V, –4.0V
+1.0V, +4.2V
0
0
–50
–100
–5
+1.0, –6.0V
–10
–15
–20
–150
–3.5V, –8.7V
+3.5V, –15.5V
REPRESENTATIVE SAMPLES
–200
–4
–3
–2
–1
0
1
2
3
4
–50
–30
–10
10
30
50
70
90
110
130
OUTPUT VOLTAGE (V)
TEMPERATURE (°C)
Figure 6. System Offset vs. Temperature, Normalized at 25°C,
Referred to Output, Gain = ½
Figure 9. Input Common-Mode Voltage vs. Output Voltage,
Gain = ½, 5 V and 2.5 V Supplies
25
30
20
0V, +20.85V
G = 2
20
15
V
= ±15V
S
10
10
+13.5V, +11.5V
–13.5V, +11.5V
0
5
–10
–20
–30
0
–5
+13.5V, –11.5V
–10
–15
–20
–25
–13.5V, –11.5V
–40
REPRESENTATIVE SAMPLES
0V, –20.85V
0
–50
–50
–15
–10
–5
5
10
15
–30
–10
10
30
50
70
90
110
130
OUTPUT VOLTAGE (V)
TEMPERATURE (°C)
Figure 10. Input Common-Mode Voltage vs. Output Voltage,
Gain = 2, 15 V Supplies
Figure 7. Gain Error vs. Temperature, Normalized at 25°C, Gain = ½
Rev. C | Page 6 of 16
AD8274
8
6
10
5
–3.5V, +6.9V
G = 2
V
= ±5V
S
G = 2
+3.5V, +5.2V
4
V
= ±2.5V
S
–1.0V, +2.7V
0
+1.0V, +2.2V
2
G = ½
–5
0
–1.0V, –2.0V
–2
–4
–6
–8
+1.0, –2.6V
–10
–15
–20
–3.5V, –5.2V
+3.5V, –6.9V
–4
–3
–2
–1
0
1
2
3
4
100
1k
10k
100k
1M
10M
100M
OUTPUT VOLTAGE (V)
FREQUENCY(Hz)
Figure 11. Input Common-Mode Voltage vs. Output Voltage,
Gain = 2, 5 V and 2.5 V Supplies
Figure 14. Gain vs. Frequency
140
120
100
80
60
40
20
0
POSITIVE PSRR
GAIN = 2
GAIN = ½
120
100
80
60
40
20
0
NEGATIVE PSRR
10
100
1k
10k
100k
1M
1
10
100
1k
10k
100k
1M
FREQUENCY (Hz)
FREQUENCY (Hz)
Figure 12. Power Supply Rejection Ratio vs. Frequency,
Gain = ½, Referred to Output
Figure 15. Common-Mode Rejection Ratio vs. Frequency, Referred to Input
120
32
28
24
20
16
12
8
±15V SUPPLY
100
SOURCING
80
60
40
20
0
–20
±5V SUPPLY
–40
SINKING
–60
–80
4
–100
–40
0
100
–20
0
20
40
60
80
100
120
1k
10k
100k
1M
10M
TEMPERATURE (°C)
FREQUENCY (Hz)
Figure 16. Short-Circuit Current vs. Temperature
Figure 13. Maximum Output Voltage vs. Frequency
Rev. C | Page 7 of 16
AD8274
+V
S
+85°C
+25°C
+125°C
C
= 100pF
L
+V – 2
S
–40°C
+V – 4
S
0
NO LOAD
–V + 4
S
+125°C
+25°C
600Ω
2kΩ
–V + 2
S
–40°C
+85°C
–V
S
1µs/DIV
200
1k
LOAD RESISTANCE (Ω)
10k
Figure 20. Small-Signal Step Response, Gain = ½
Figure 17. Output Voltage Swing vs. RL, VS = 15 V
+V
S
–40°C
+25°C
+V – 3
S
+V – 6
S
+125°C
+85°C
+125°C
–V + 6
S
+85°C
+25°C
–V + 3
S
–40°C
–V
S
0
20
40
60
80
100
1µs/DIV
CURRENT (mA)
Figure 21. Small-Signal Pulse Response with 500 pF Capacitor Load,
Gain = 2
Figure 18. Output Voltage vs. IOUT
C
= 100pF
L
NO LOAD
600Ω
2kΩ
1µs/DIV
1µs/DIV
Figure 22. Small-Signal Pulse Response for 100 pF Capacitive Load,
Gain = ½
Figure 19. Small-Signal Step Response, Gain = 2
Rev. C | Page 8 of 16
AD8274
100
90
80
70
60
50
40
30
20
10
0
100
90
80
70
60
50
40
30
20
10
0
2.5V
5V
15V
2.5V
15V
5V
18V
18V
0
200
400
600
800
1000
1200
0
20
40
60
80
100 120 140 160 180 200
CAPACITIVE LOAD (pF)
CAPACITIVE LOAD (pF)
Figure 26. Small-Signal Overshoot vs. Capacitive Load,
Gain = 2, 600 Ω in Parallel with Capacitive Load
Figure 23. Small-Signal Overshoot vs. Capacitive Load,
Gain = ½, No Resistive Load
100
90
80
70
60
50
40
30
20
10
0
2.5V
5V
15V
18V
0
20
40
60
80
100 120 140 160 180 200
1µs/DIV
CAPACITIVE LOAD (pF)
Figure 24. Small-Signal Overshoot vs. Capacitive Load,
Gain = ½, 600 Ω in Parallel with Capacitive Load
Figure 27. Large-Signal Pulse Response,
Gain = ½
100
90
80
70
60
50
40
30
20
10
0
2.5V
5V
15V
18V
0
200
400
600
800
1000
1200
1µs/DIV
CAPACITIVE LOAD (pF)
Figure 28. Large-Signal Pulse Response,
Gain = 2
Figure 25. Small-Signal Overshoot vs. Capacitive Load,
Gain = 2, No Resistive Load
Rev. C | Page 9 of 16
AD8274
40
35
30
25
20
15
10
5
0.1
0.01
22kHz FILTER
= 10V p-p
V
OUT
= 600Ω
R
L
+SR
–SR
0.001
0.0001
GAIN = 2
GAIN = ½
0
–40
–20
0
20
40
60
80
100
120
10
100
1k
FREQUENCY (Hz)
10k
100k
TEMPERATURE (°C)
Figure 32. THD + N vs. Frequency, Filter = 22k Hz
Figure 29. Slew Rate vs. Temperature
0.1
0.01
10k
1k
V
= 10V p-p
OUT
GAIN = 2
GAIN = ½
100
0.001
0.0001
GAIN = 2
GAIN = ½
10
1
10
100
1k
10k
100k
10
100
1k
10k
100k
FREQUENCY (Hz)
FREQUENCY (Hz)
Figure 33. THD + N vs. Frequency, Filter = 120 kHz
Figure 30. Voltage Noise Density vs. Frequency, Referred to Output
1
0.1
GAIN = ½
f = 1kHz
G = 2
R
= 2kΩ, 100Ω
L
0.01
G = ½
R
= 600Ω
L
0.001
0.0001
0
5
10
15
20
25
1s/DIV
OUTPUT AMPLITUDE (dBu)
Figure 31. 0.1 Hz to 10 Hz Voltage Noise, RTO
Figure 34. THD + N vs. Output Amplitude, G = ½
Rev. C | Page 10 of 16
AD8274
1
0.1
0.1
0.01
GAIN = 2
f = 1kHz
GAIN = 2
= 10V p-p
V
OUT
0.01
0.001
R
R
R
= 600Ω
= 2kΩ
= 100kΩ
L
L
L
THIRD HARMONIC ALL LOADS
0.001
0.0001
0.0001
0.00001
SECOND HARMONIC R = 600Ω
L
SECOND HARMONIC R = 100kΩ, 2kΩ
L
0
5
10
15
20
25
10
100
1k
10k
100k
OUTPUT AMPLITUDE (dBu)
FREQUENCY (Hz)
Figure 35. THD + N vs. Output Amplitude, G = 2
Figure 37. Harmonic Distortion Products vs. Frequency, G = 2
0.1
GAIN = ½
V
= 10V p-p
OUT
0.01
0.001
THIRD HARMONIC ALL LOADS
0.0001
0.00001
SECOND HARMONIC R = 600Ω
L
SECOND HARMONIC R = 100kΩ, 2kΩ
L
10
100
1k
10k
100k
FREQUENCY (Hz)
Figure 36. Harmonic Distortion Products vs. Frequency, G = ½
Rev. C | Page 11 of 16
AD8274
THEORY OF OPERATION
+V
S
DRIVING THE AD8274
7
The AD8274 is easy to drive, with all configurations presenting
at least several kilohms (kꢀ) of input resistance. The AD8274
should be driven with a low impedance source: for example,
another amplifier. The gain accuracy and common-mode rejection
of the AD8274 depend on the matching of its resistors. Even
source resistance of a few ohms can have a substantial effect on
these specifications.
12kΩ
6kΩ
2
5
6
12kΩ
6kΩ
3
1
4
–V
S
POWER SUPPLIES
Figure 38. Functional Block Diagram
A stable dc voltage should be used to power the AD8274. Noise
on the supply pins can adversely affect performance. A bypass
capacitor of 0.1 μF should be placed between each supply pin
and ground, as close as possible to each supply pin. A tantalum
capacitor of 10 μF should also be used between each supply and
ground. It can be farther away from the supply pins and, typically,
it can be shared by other precision integrated circuits.
CIRCUIT INFORMATION
The AD8274 consists of a high precision, low distortion op amp
and four trimmed resistors. These resistors can be connected to
make a wide variety of amplifier configurations, including
difference, noninverting, and inverting configurations. Using
the on-chip resistors of the AD8274 provides the designer with
several advantages over a discrete design.
The AD8274 is specified at 15 V, but it can be used with
unbalanced supplies, as well. For example, −VS = 0 V, +VS = 20 V.
The difference between the two supplies must be kept below 36 V.
DC Performance
Much of the dc performance of op amp circuits depends on the
accuracy of the surrounding resistors. The resistors on the AD8274
are laid out to be tightly matched. The resistors of each part are
laser trimmed and tested for their matching accuracy. Because
of this trimming and testing, the AD8274 can guarantee high
accuracy for specifications such as gain drift, common-mode
rejection, and gain error.
INPUT VOLTAGE RANGE
The AD8274 can measure voltages beyond the rails. For the G = ½
and G = 2 difference amplifier configurations, see the input voltage
range in Table 2 for specifications.
The AD8274 is able to measure beyond the rail because the
internal resistors divide down the voltage before it reaches the
internal op amp. Figure 39 shows an example of how the voltage
division works in the difference amplifier configuration. For the
AD8274 to measure correctly, the input voltages at the internal
op amp must stay within 1.5 V of either supply rail.
R2
AC Performance
Because feature size is much smaller in an integrated circuit than
on a printed circuit board (PCB), the corresponding parasitics are
also smaller. The smaller feature size helps the ac performance of
the AD8274. For example, the positive and negative input terminals
of the AD8274 op amp are not pinned out intentionally. By not
connecting these nodes to the traces on the PCB, the capacitance
remains low, resulting in both improved loop stability and
common-mode rejection over frequency.
(V
)
IN+
R1 + R2
R4
R3
R1
R2
Production Costs
R2
R1 + R2
Because one part, rather than several, is placed on the PCB, the
board can be built more quickly.
(V
)
IN+
Figure 39. Voltage Division in the Difference Amplifier Configuration
Size
For best long-term reliability of the part, voltages at any of the
part’s inputs (Pin 1, Pin 2, Pin 3, or Pin 5) should stay within
+VS – 40 V to −VS + 40 V. For example, on 10 V supplies,
input voltages should not exceed 30 V.
The AD8274 fits a precision op amp and four resistors in one
8-lead MSOP or SOIC package.
Rev. C | Page 12 of 16
AD8274
CONFIGURATIONS
The AD8274 can be configured in several ways; see Figure 40 to Figure 47. Because these configurations rely on the internal, matched
resistors, all of these configurations have excellent gain accuracy and gain drift. Note that the AD8274 internal op amp is stable for noise
gains of 1.5 and higher, so the AD8274 should not be placed in a unity-gain follower configuration.
12kΩ
12kΩ
6kΩ
12kΩ
6kΩ
2
3
5
6
2
5
6
–IN
OUT
OUT
6kΩ
12kΩ
6kΩ
3
1
1
+IN
+IN
V
= ½ (V
IN+
− V )
IN−
OUT
V
= ½ V
IN
OUT
Figure 44. Noninverting Amplifier, G = ½
Figure 40. Difference Amplifier, G = ½
6kΩ
6kΩ
12kΩ
12kΩ
6kΩ
6kΩ
12kΩ
12kΩ
5
1
2
6
5
1
2
6
–IN
+IN
OUT
OUT
3
3
+IN
V
= 2 (V
IN+
− V )
IN−
OUT
V
= 2 V
IN
OUT
Figure 41. Difference Amplifier, G = 2
Figure 45. Noninverting Amplifier, G = 2
12kΩ
6kΩ
12kΩ
6kΩ
2
5
6
2
5
6
–IN
OUT
OUT
6kΩ
6kΩ
1
1
3
+IN
12kΩ
12kΩ
3
V
= 1½ V
IN
OUT
V
= –½ V
IN
OUT
Figure 46. Noninverting Amplifier, G = 1.5
Figure 42. Inverting Amplifier, G = −½
6kΩ
12kΩ
6kΩ
12kΩ
5
2
5
2
6
–IN
OUT
OUT
6
12kΩ
6kΩ
3
12kΩ
6kΩ
1
+IN
3
1
V
= 3 V
OUT
IN
V
= –2 V
IN
OUT
Figure 47. Noninverting Amplifier, G = 3
Figure 43. Inverting Amplifier, G = −2
Rev. C | Page 13 of 16
AD8274
DRIVING CABLING
Because the AD8274 can drive large voltages at high output
currents and slew rates, it makes an excellent cable driver. It is
good practice to put a small value resistor between the AD8274
output and cable, since capacitance in the cable can cause peaking
or instability in the output response. A resistance of 20 Ω or higher
is recommended.
R ≥ 20Ω
AD8274
Figure 48. Driving Cabling
Rev. C | Page 14 of 16
AD8274
OUTLINE DIMENSIONS
5.00 (0.1968)
4.80 (0.1890)
8
1
5
4
6.20 (0.2441)
5.80 (0.2284)
4.00 (0.1574)
3.80 (0.1497)
0.50 (0.0196)
0.25 (0.0099)
1.27 (0.0500)
BSC
45°
1.75 (0.0688)
1.35 (0.0532)
0.25 (0.0098)
0.10 (0.0040)
8°
0°
0.51 (0.0201)
0.31 (0.0122)
COPLANARITY
0.10
1.27 (0.0500)
0.40 (0.0157)
0.25 (0.0098)
0.17 (0.0067)
SEATING
PLANE
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.
Figure 49. 8-Lead Standard Small Outline Package [SOIC_N]
Narrow Body (R-8)
Dimensions shown in millimeters and (inches)
3.20
3.00
2.80
8
1
5
4
5.15
4.90
4.65
3.20
3.00
2.80
PIN 1
IDENTIFIER
0.65 BSC
0.95
0.85
0.75
15° MAX
1.10 MAX
0.80
0.55
0.40
0.15
0.05
0.23
0.09
6°
0°
0.40
0.25
COPLANARITY
0.10
COMPLIANT TO JEDEC STANDARDS MO-187-AA
Figure 50. 8-Lead Mini Small Outline Package [MSOP]
(RM-8)
Dimensions shown in millimeters
ORDERING GUIDE
Model1
Temperature Range
Package Description
Package Option
Branding
AD8274ARZ
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
8-Lead SOIC_N
R-8
R-8
R-8
RM-8
RM-8
RM-8
AD8274ARZ-R7
AD8274ARZ-RL
AD8274ARMZ
AD8274ARMZ-R7
AD8274ARMZ-RL
8-Lead SOIC_N, 7" Tape and Reel
8-Lead SOIC_N, 13" Tape and Reel
8-Lead MSOP
8-Lead MSOP, 7" Tape and Reel
8-Lead MSOP, 13" Tape and Reel
Y1B
Y1B
Y1B
1 Z = RoHS Compliant Part.
Rev. C | Page 15 of 16
AD8274
NOTES
©2008–2011 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D07362-0-8/11(C)
Rev. C | Page 16 of 16
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