Datasheet AD8274 Datasheet (ANALOG DEVICES)

Very Low Distortion,

V

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FEATURES

Very low distortion

0.00025% THD + N (20 kHz)

0.0015% THD + N (100 kHz)
Drives 600 Ω loads

Excellent gain accuracy

0.03% maximum gain error
2 ppm/°C maximum gain drift
Gain of ½ or 2

AC specifications

20 V/μs minimum slew rate
800 ns to 0.01% settling time

High accuracy dc performance

83 dB minimum CMRR

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

APPLICATIONS

ADC driver
High performance audio
Instrumentation amplifier building blocks
Level translators
Automatic test equipment
Sine/cosine encoders

Precision Difference Amplifier

AD8274

FUNCTIONAL BLOCK DIAGRAM

+

S

7

12kΩ 6kΩ

2

12kΩ

3 1

4

–V

S

Figure 1.

Table 1. Difference Amplifiers by Category

Low
Distortion

AD8270 AD628 AD8202 AD8205
AD8273 AD629 AD8203 AD8206

AD8274 AD8216

AMP03

High
Voltage

Single-Supply
Unidirectional

6kΩ

5

6

07362-001

Single-Supply
Bidirectional

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.

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  load

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.

Rev. 0

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.

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.

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.

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.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] www.analog.com
Fax: [phone] ©2008 Analog Devices, Inc. All rights reserved.

AD8274

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TABLE OF CONTENTS

Features .............................................................................................. 1

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

7/08—Revision 0: Initial Version

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

Rev. 0 | Page 2 of 16

AD8274

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SPECIFICATIONS

VS = ±15 V, V

Table 2.

G = ½ G = 2
Parameter Conditions Min Typ Max Min Typ Max Unit

DYNAMIC PERFORMANCE

Bandwidth 20 10 MHz

Slew Rate 20 20 V/μs

Settling Time to 0.1% 10 V step on output, CL = 100 pF 650 750 675 775 ns

Settling Time to 0.01% 10 V step on output, CL = 100 pF 725 800 750 825 ns

NOISE/DISTORTION

THD + Noise

Noise Floor, RTO

Output Voltage Noise

(Referred to Output)

f = 1 kHz 26 52 nV/√Hz

GAIN

Gain Error 0.03 0.03 %

Gain Drift −40°C to +85°C 0.5 2 0.5 2 ppm/°C

Gain Nonlinearity V

INPUT CHARACTERISTICS

3

Offset

vs. Temperature −40°C to +85°C 3 6 μV/°C
vs. Power Supply VS = ±2.5 V to ±18 V 5 10 μV/V

Common-Mode Rejection Ratio

Input Voltage Range

Impedance

Differential VCM = 0 V 24 12 kΩ
Common Mode

OUTPUT CHARACTERISTICS

Output Swing

Short-Circuit Current Limit Sourcing 90 90 mA

Sinking 60 60 mA

Capacitive Load Drive 200 1200 pF

POWER SUPPLY

Supply Current (per Amplifier) 2.3 2.6 2.3 2.6 mA

TEMPERATURE RANGE

Specified Performance −40 +85 −40 +85 °C

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.

= 0 V, TA = 25°C, RL = 2 kΩ, unless otherwise noted.

REF

1

f = 1 kHz, V

= 10 V p-p,

OUT

0.00025 0.00035 %

600 Ω load

2

20 kHz BW −106 −100 dBu
f = 20 Hz to 20 kHz 3.5 7 μV rms

= 10 V p-p, 600 Ω load 2 2 ppm

OUT

Referred to output 150 700 300 1100 μV

= ±40 V, RS = 0 Ω, referred

V

CM

77 86 83 92 dB

to input

4

−3V
+ 4.5

5

6

9 9 kΩ

−V

1.5

S

+

S

+3VS

− 4.5

+V

S

1.5

−

−1.5VS
+ 2.3

−VS +

1.5

+1.5VS

V

− 2.3

+V

S

−

V

1.5

Rev. 0 | Page 3 of 16

AD8274

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ABSOLUTE MAXIMUM RATINGS

Table 3.

Parameter Rating

Supply Voltage ±18 V
Maximum Voltage at Any Input Pin −VS + 40 V
Minimum Voltage at Any Input Pin +VS – 40 V
Storage Temperature Range −65°C to +150°C
Specified Temperature Range −40°C to +85°C
Package Glass Transition Temperature (TG) 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.

THERMAL RESISTANCE

The θJA values in Tabl e 4 assume a 4-layer JEDEC standard
board with zero airflow.

MAXIMUM POWER DISSIPATION

The maximum safe power dissipation for the AD8274 is limited
by the associated rise in junction temperature (T
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

TJ MAX = 150°C

1.6

1.2

MSOP

θ

= 135°C/W

0.8

0.4

MAXIMUM POWER DISSIPATIO N (W)

JA

SOIC

= 121°C/W

θ

JA

) on the die. At

J

Table 4. Thermal Resistance

Package Type θJA Unit

8-Lead MSOP 135 °C/W
8-Lead SOIC 121 °C/W

0

–50 0–25 25 50 75 100 125

Figure 2. Maximum Power Dissipation vs. Ambient Temperature

AMBIENT TEM ERATURE (°C)

07362-004

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. 0 | Page 4 of 16

AD8274

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PIN CONFIGURATIONS AND FUNCTION DESCRIPTION

REF

1

AD8274

2

–IN

TOP VIEW

+IN

3

(Not to Scal e)

–V

4

S

NC = NO CONNECT

Figure 3. MSOP Pin Configuration

Table 5. Pin Function Descriptions

Pin No. Mnemonic Description

1 REF

2 −IN

3 +IN

4 −VS Negative Supply.
5 SENSE

6 OUT Output.
7 +VS Positive Supply.
8 NC No Connect.

NC

8

7

6

5

+V

S

OUT

SENSE

07362-002

REF

1

–IN

2

+IN

3

(Not to Scale)

4

–V

S

NC = NO CONNECT

AD8274

TOP VIEW

8

7

6

5

NC

+V

S

OUT

SENSE

07362-003

Figure 4. SOIC Pin Configuration

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.

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.

6 kΩ Resistor to Inverting Terminal of Op Amp. Connect to output in G = ½ configuration. Used as
negative input in G = 2 configuration.

Rev. 0 | Page 5 of 16

AD8274

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TYPICAL PERFORMANCE CHARACTERISTICS

VS = ±15 V, TA = 25°C, gain = ½, difference amplifier configuration, unless otherwise noted.

20

15

10

5

0

–5

CMR (µV/V)

–10

–15

–20

–25

REPRESENTATIVE SAMPLES

–30

–50 –30 10 50 130

–10 30 70 90 110

TEMPERATURE ( °C)

Figure 5. CMR vs. Temperature, Normalized at 25°C, Gain = ½

07362-106

25

20

15

10

–13.5V, +11. 5V

5

0

–5

–13.5V, –11.5V

–10

–15

INPUT COMMON-MODE VO LTAGE (V)

–20

–25

–15 –10 –5 0 5 10 15

0V, +20.85V

VS = ±15V

0V, –20.85V

OUTPUT VO LTAGE (V)

G = 2

+13.5V, + 11.5V

+13.5V, –11. 5V

Figure 8. Input Common-Mode Voltage vs. Output Voltage,

Gain = ½, ±15 V Supplies

07362-111

150

100

50

0

–50

SYSTEM OFFSET (µV)

–100

–150

REPRESENTATIVE SAMPLES

–200

–50 –30 10 50 130

–10 30 70 90 110

TEMPERATURE ( °C)

Figure 6. System Offset vs. Temperature, Normalized at 25°C,

Referred to Output, Gain = ½

30

20

10

0

–10

20

–3.5V, +15. 8V

15

10

5

0

–5

–10

INPUT COMMON-MODE VOLTAGE (V)

–15

07362-107

–20

–4–3–2–101234

–1.0V, +6. 2V

–1.0V, –4. 0V

–3.5V, –8.7V

VS = ±5V

VS = ±2.5V

+1.0V, +4.2V

+1.0, –6.0V

OUTPUT VO LTAGE (V)

G = ½

+3.5V, +8.8V

+3.5V, –15. 5V

07362-110

Figure 9. Input Common-Mode Voltage vs. Output Voltage,

Gain = ½, ±5 V and ±2.5 V Supplies

3

0

2

0

1

0

0

0V, +25V

VS = ±15V

–13.5V, +11. 5V

G = ½

+13.5V, +11. 5V

–20

GAIN ERROR (µ V/V)

–30

–40

REPRESENTATIVE SAMPLES

–50

–50 –30 10 50 130

–10 30 70 90 110

TEMPERATURE ( °C)

Figure 7. Gain Error vs. Temperature, Normalized at 25°C, Gain = ½

INPUT COMMON-MODE VOLTAGE (V)

07362-108

–13.5V, –11.5V

–

1

0

–

2

0

–

3

0

–15 –10 –5 0 5 10 15

OUTPUT VO LTAGE (V)

Figure 10. Input Common-Mode Voltage vs. Output Voltage,

Gain = 2, ±15 V Supplies

Rev. 0 | Page 6 of 16

0V, –25V

+13.5V, –11. 5V

07362-210

AD8274

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8

–3.5V, +6. 9V

6

4

2

0

–2

–4

INPUT COMMON-MODE VOL TAGE (V)

–6

–8

–4–3–2–101234

–1.0V, +2. 7V

–1.0V, –2. 0V

–3.5V, –5.2V

VS = ±5V

VS = ±2.5V

OUTPUT VOLTAGE (V)

+1.0V, +2.2V

Figure 11. Input Common-Mode Voltage vs. Output Voltage,

Gain = 2, ±5 V and ±2.5 V Supplies

140

POSITIVE PSRR

120

100

NEGATIVE PS RR

80

60

40

POWER SUPPL Y REJECTIO N (dB)

20

+3.5V, +5. 2V

+1.0, –2.6V

G = 2

+3.5V, –6. 9V

10

G = 2

5

0

–5

GAIN (dB)

–10

–15

07362-112

–20

1k100 10k 100k 1M 100M10M

G = ½

FREQUENCY(Hz)

07362-007

Figure 14. Gain vs. Frequency

120

100

80

60

CMRR (dB)

40

20

GAIN = 2

GAIN = ½

0

100 1M100k10k1k110

FREQUENCY (Hz)

Figure 12. Power Supply Rejection Ratio vs. Frequency,

Gain = ½, Referred to Output

32

±15V SUPPLY

28

24

20

16

12

±5V SUPPLY

8

MAXIMUM OUTPUT VOLTAGE (V p-p)

4

0

1k100 10k 100k 1M 10M

FREQUENCY (Hz)

Figure 13. Maximum Output Voltage vs. Frequency

0

07362-021

1k10010 10k 100k 1M

FREQUENCY (Hz)

7362-217

Figure 15. Common-Mode Rejection Ratio vs. Frequency, Referred to Input

120

100

80

60

40

20

0

–20

–40

SHORT-CIRCUIT CURRENT (mA)

–60

–80

–100

–40 –20 20 60

7362-006

04080100 120

TEMPERATURE ( °C)

SOURCING

SINKING

07362-117

Figure 16. Short-Circuit Current vs. Temperature

Rev. 0 | Page 7 of 16

AD8274

V

V

www.BDTIC.com/ADI

+

+VS– 2

+V

–V

OUTPUT VOLT AGE SWING (V)

–V

+VS – 3

+V

S

+125° C

–40°C

– 4

S

0

+ 2

S

+ 4

S

–V

S

–40°C

+125°C

+25°C

+85°C

Figure 17. Output Voltage Swing vs. RL, VS = ±15 V

+

S

– 6

S

+85°C

+25°C

1k200 10k

LOAD RESIST ANCE (Ω)

–40°C

+125°C

+25°C

+85°C

CL = 100pF

50mV/DIV

07362-009

600Ω

NO LOAD

2kΩ

1µs/DIV

07362-025

Figure 20. Small-Signal Step Response, Gain = ½

NO LOAD

2kΩ

+125°C

CURRENT (mA)

1µs/DIV

+85°C

+25°C

–40°C

OUT

–VS + 6

OUTPUT VOLTAGE (V)

–V

+ 3

S

–V

S

0 2040608010

Figure 18. Output Voltage vs. I

CL = 100pF

50mV/DIV

600Ω

Figure 19. Small-Signal Step Response, Gain = 2

0

7362-023

07362-024

50mV/DIV

1µs/DIV

07362-026

Figure 21. Small-Signal Pulse Response with 500 pF Capacitor Load,

Gain = 2

50mV/DIV

1µs/DIV

7362-027

Figure 22. Small-Signal Pulse Response for 100 pF Capacitive Load,

Gain = ½

Rev. 0 | Page 8 of 16

AD8274

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100

90

80

70

60

50

40

OVERSHOOT (%)

30

20

10

0

0 2 0 40 60 80 100 120 140 160 180 200

CAPACI TIVE LOAD (pF)

2.5V

5V

15V

18V

Figure 23. Small-Signal Overshoot vs. Capacitive Load,

Gain = ½, No Resistive Load

100

90

80

70

60

50

40

OVERSHOOT (%)

30

20

10

0

0 2 0 40 60 80 100 120 140 160 180 200

CAPACI TIVE LOAD (pF)

2.5V
5V

15V

18V

Figure 24. Small-Signal Overshoot vs. Capacitive Load,

Gain = ½, 600 Ω in Parallel with Capacitive Load

07362-037

07362-038

100

90

80

70

60

50

40

OVERSHOOT (%)

30

20

10

0

0 200 400 600 800 1000 1200

CAPACITIVE L OAD (pF)

18V

2.5V

Figure 26. Small-Signal Overshoot vs. Capacitive Load,

Gain = 2, 600 Ω in Parallel with Capacitive Load

2V/DIV

1µs/DIV

Figure 27. Large-Signal Pulse Response,

Gain = ½

15V

5V

07362-040

07362-032

100

90

80

70

60

50

40

OVERSHOOT (%)

30

20

10

0

0 200 400 600 800 1000 1200

CAPACITIVE LOAD (pF)

Figure 25. Small-Signal Overshoot vs. Capacitive Load,

18V

2.5V

5V

15V

2V/DIV

07362-039

Figure 28. Large-Signal Pulse Response,

Gain = 2, No Resistive Load

Rev. 0 | Page 9 of 16

1µs/DIV

Gain = 2

07362-033

AD8274

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40

35

30

25

+SR

20

–SR

15

SLEW RATE (V/µS)

10

5

0

–40 –20 0 20 40 60 80 100 120

TEMPERATURE ( °C)

Figure 29. Slew Rate vs. Temperature

10k

1k

7362-010

0.1

22kHz FILTER
V

= 10V p-p

OUT

R

= 600Ω

L

0.01

THDN + N (%)

0.001

GAIN = 2

GAIN = ½

0.0001
10

100

FREQUENCY (Hz)

1k 10k

Figure 32. THD + N vs. Frequency, Filter = 22k Hz

0.1

V

= 10V p-p

OUT

0.01

100k

07362-131

100

VOLTAGE NOISE DENSITY (nV/ √Hz)

10

GAIN = 2

GAIN = ½

1 10 100 1k 10k 100k

FREQUENCY (Hz)

Figure 30. Voltage Noise Density vs. Frequency, Referred to Output

G = 2

1µV/DIV

G = ½

1s/DIV

Figure 31. 0.1 Hz to 10 Hz Voltage Noise, RTO

THD + N (%)

0.001

0.0001

07362-034

GAIN = 2

GAIN = ½

10

100

1k 10k

FREQUENCY (Hz)

100k

07362-135

Figure 33. THD + N vs. Frequency, Filter = 120 kHz

1

GAIN = ½

f = 1kHz

0.1

R

= 2kΩ, 100Ω

0.01

THD + N (%)

0.001

0.0001

07362-035

0

10 15

OUTPUT AMPL ITUDE (dBu)

L

RL = 600Ω

20

255

7362-136

Figure 34. THD + N vs. Output Amplitude, G = ½

Rev. 0 | Page 10 of 16

AD8274

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0.1

1

GAIN = 2

f = 1kHz

0.1

0.01

GAIN = 2
V

= 10V p-p

OUT

0.01

THD + N (%)

0.001

0.0001

= 600Ω

R

L

R

= 2kΩ

L

R

= 100kΩ

L

0

10 15

OUTPUT AMPL ITUDE (dBu)

Figure 35. THD + N vs. Output Amplitude, G = 2

0.1

GAIN = ½
V

= 10V p-p

OUT

0.01

0.001

THIRD HARMONIC ALL LOADS

0.0001
SECOND HARMONIC RL = 600Ω

AMPLITUDE ( % OF FUNDAMENT AL)

0.00001

SECOND HARMONIC RL = 100kΩ, 2kΩ

10

100

FREQUENCY (Hz)

1k 10k

Figure 36. Harmonic Distortion Products vs. Frequency, G = ½

0.001

THIRD HARMONIC ALL LOADS

0.0001
SECOND HARMONIC RL = 600Ω

AMPLITUDE ( % OF FUNDAMENT AL)

20

255

7362-137

0.00001

SECOND HARMONIC RL = 100kΩ, 2kΩ

10

100

FREQUENCY (Hz)

1k 10k

100k

07362-139

Figure 37. Harmonic Distortion Products vs. Frequency, G = 2

100k

07362-138

Rev. 0 | Page 11 of 16

AD8274

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THEORY OF OPERATION

+

S

7

12kΩ 6kΩ

2

12kΩ

3 1

4

–V

S

Figure 38. Functional Block Diagram

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.

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.

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.

Production Costs

Because one part, rather than several, is placed on the PCB, the
board can be built more quickly.

Size

The AD8274 fits a precision op amp and four resistors in one
8-lead MSOP or SOIC package.

6kΩ

5

6

07362-001

DRIVING THE AD8274

The AD8274 is easy to drive, with all configurations presenting
at least several kilohms (kΩ) 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.

POWER SUPPLIES

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.

The AD8274 is specified at ±15 V, but it can be used with
unbalanced supplies, as well. For example, −V

= 0 V, +VS = 20 V.

S

The difference between the two supplies must be kept below 36 V.

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 Tab l e 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

(V

)

IN+

R1 + R2

R4

R3

R1

R2

R2

(V

)

IN+

R1 + R2

Figure 39. Voltage Division in the Difference Amplifier Configuration

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
+V

– 40 V to −VS + 40 V. For example, on ±10 V supplies,

S

input voltages should not exceed ±30 V.

07362-061

Rev. 0 | Page 12 of 16

AD8274

V

V

V

V

+

www.BDTIC.com/ADI

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.

–IN

+IN

V

OUT

12kΩ

2

12kΩ 6kΩ

3

= ½ (V

IN+

− V

6kΩ

5

OUT

6

1

)

IN−

Figure 40. Difference Amplifier, G = ½

–IN

+IN

OUT

6kΩ

5

6kΩ 12kΩ

1

= 2 (V

IN+

− V

12kΩ

2

OUT

6

3

)

IN−

Figure 41. Difference Amplifier, G = 2

–IN

12kΩ

2

6kΩ

1

12kΩ

3

V

= –½ V

OUT

6kΩ

5

OUT

6

IN

Figure 42. Inverting Amplifier, G = −½

12kΩ

2

12kΩ 6kΩ

3

+IN

07362-012

OUT

= ½ V

IN

6kΩ

5

OUT

6

1

07362-015

Figure 44. Noninverting Amplifier, G = ½

6kΩ

5

6kΩ 12kΩ

1

07362-016

+IN

OUT

= 2 V

IN

12kΩ

2

OUT

6

3

07362-019

Figure 45. Noninverting Amplifier, G = 2

12kΩ

25

6kΩ

1

IN

12kΩ

3

07362-013

V

= 1½ V

OUT

Figure 46. Noninverting Amplifier, G = 1.5

6kΩ

OUT

6

IN

07362-014

6kΩ

5

–IN

12kΩ

1

6kΩ

3

= –2 V

OUT

IN

Figure 43. Inverting Amplifier, G = −2

12kΩ

2

OUT

6

+IN

V

= 3 V

07362-017

OUT

Figure 47. Noninverting Amplifier, G = 3

Rev. 0 | Page 13 of 16

6kΩ

5

12kΩ

3

6kΩ

1

IN

12kΩ

2

OUT

6

07362-018

AD8274

www.BDTIC.com/ADI

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  or higher
is recommended.

AD8274

Figure 48. Driving Cabling

R ≥ 20Ω

06979-060

Rev. 0 | Page 14 of 16

AD8274

www.BDTIC.com/ADI

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)

COPLANARITY

0.10

CONTROLL ING DIMENSI ONS ARE IN MILLIMETERS; INCH DI MENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRI ATE FOR USE IN DESIGN.

85

1

1.27 (0.0500)

SEATING

PLANE

COMPLIANT TO JEDEC STANDARDS MS-012-A A

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°

012407-A

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

5

4

SEATING
PLANE

5.15

4.90

4.65

1.10 MAX

0.23

0.08

8°
0°

0.80

0.60

0.40

3.20

3.00

2.80

PIN 1

0.95

0.85

0.75

0.15

0.00

COPLANARITY

1

0.65 BSC

0.38

0.22

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

Model Temperature Range Package Description Package Option Branding

AD8274ARZ
AD8274ARZ-R7
AD8274ARZ-RL
AD8274ARMZ
AD8274ARMZ-R7
AD8274ARMZ-RL

1

Z = RoHS Compliant Part.

1

−40°C to +85°C 8-Lead SOIC_N R-8

1

−40°C to +85°C 8-Lead SOIC_N, 7" Tape and Reel R-8

1

−40°C to +85°C 8-Lead SOIC_N, 13" Tape and Reel R-8

1

−40°C to +85°C 8-Lead MSOP RM-8 Y1B

1

−40°C to +85°C 8-Lead MSOP, 7" Tape and Reel RM-8 Y1B

1

−40°C to +85°C 8-Lead MSOP, 13" Tape and Reel RM-8 Y1B

Rev. 0 | Page 15 of 16

AD8274

www.BDTIC.com/ADI

NOTES

©2008 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D07362-0-7/08(0)

Rev. 0 | Page 16 of 16