Analog Devices AD8574, AD8572, AD8571 Datasheet

Zero-Drift, Single-Supply, Rail-to-Rail

1
2
3
4

8
7
6
5

AD8571

2IN A

V2

+IN A

V+
OUT A

NC

NC

NC

NC = NO CONNECT

1
2
3
4

8
7
6
5

AD8572

2IN A

V2

+IN A

OUT B

2IN B

V+

+IN B

OUT A

14

13

12

11

10

9

8

1

2

3

4

5

6

7

2IN A

+IN A

V+

+IN B

2IN B

OUT B

OUT D

2IN D

+IN D

V2

+IN C

2IN C

OUT C

OUT A

AD8574

2IN A
1IN A

V2

V+
OUT A

NC

1

45

8

AD8571

NC

NC = NO CONNECT

NC

a

Input/Output Operational Amplifiers

FEATURES
Low Offset Voltage: 1 ␮V
Input Offset Drift: 0.005 ␮V/ⴗC
Rail-to-Rail Input and Output Swing
5 V/2.7 V Single-Supply Operation
High Gain, CMRR, PSRR: 130 dB
Ultralow Input Bias Current: 20 pA
Low Supply Current: 750 ␮A/Op Amp
Overload Recovery Time: 50 ␮s
No External Capacitors Required

APPLICATIONS
Temperature Sensors
Pressure Sensors
Precision Current Sensing
Strain Gage Amplifiers
Medical Instrumentation
Thermocouple Amplifiers

GENERAL DESCRIPTION

This new family of amplifiers has ultralow offset, drift and bias
current. The AD8571, AD8572 and AD8574 are single, dual and
quad amplifiers featuring rail-to-rail input and output swings. All
are guaranteed to operate from 2.7 V to 5 V single supply.

The AD857x family provides the benefits previously found only in
expensive autozeroing or chopper-stabilized amplifiers. Using Analog
Devices’ new topology these new zero-drift amplifiers combine low
cost with high accuracy. (No external capacitors are required.) In
addition, using a patented spread-spectrum autozero technique, the
AD857x family virtually eliminates the intermodulation effects from
interaction of the chopping function with the signal frequency in ac
applications.

With an offset voltage of only 1 µV and drift of 0.005 µV/°C, the

AD8571 is perfectly suited for applications where error sources
cannot be tolerated. Position, and pressure sensors, medical
equipment, and strain gage amplifiers benefit greatly from nearly
zero drift over their operating temperature range. Many more
systems require the rail-to-rail input and output swings provided
by the AD857x family.

The AD857x family is specified for the extended industrial/automotive

(–40°C to +125°C) temperature range. The AD8571 single is

available in 8-lead MSOP and narrow 8-lead SOIC packages. The
AD8572 dual amplifier is available in 8-lead narrow SO and 8-lead
TSSOP surface mount packages. The AD8574 quad is available in
narrow 14-lead SOIC and 14-lead TSSOP packages.

AD8571/AD8572/AD8574

PIN CONFIGURATIONS

8-Lead MSOP

(RM Suffix)

8-Lead TSSOP

(RU Suffix)

V2

1

AD8572

4

OUT A

2IN A

+IN A

14-Lead TSSOP

(RU Suffix)

V1

1

AD8574

78

OUT A

2IN A
1IN A

1N B

2IN B

OUT B

8

V+
OUT B

2IN B

+IN B

5

OUT D

14

2IN D
1IN D

V2

1IN C
2IN C

OUT C

8-Lead SOIC

8-Lead SOIC

(R Suffix)

14-Lead SOIC

(R Suffix)

(R Suffix)

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
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] World Wide Web Site: http://www.analog.com
Fax: [phone] © Analog Devices, Inc., 1999

AD8571/AD8572/AD8574–SPECIFICATIONS

ELECTRICAL CHARACTERISTICS

(VS = 5 V, VCM = 2.5 V, VO = 2.5 V, TA = 25ⴗC unless otherwise noted)

Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS␣

Offset Voltage V

Input Bias Current I

Input Offset Current I

B

OS

OS

–40°C ≤ T
–40°C ≤ T
–40°C ≤ T

≤ +125°C10µV

A

≤ +125°C 1.0 1.5 nA

A

≤ +125°C 150 200 pA

A

15 µV

10 50 pA

20 70 pA

Input Voltage Range 05V
Common-Mode Rejection Ratio CMRR V

Large Signal Voltage Gain

1

A

VO

= 0 V to 5 V 120 140 dB

CM

–40°C ≤ T

R

= 10 kΩ , V

L

–40°C ≤ T

≤ +125°C 115 130 dB

A

= 0.3 V to 4.7 V 125 145 dB

O

≤ +125°C 120 135 dB

A

Offset Voltage Drift ∆VOS/∆T –40°C ≤ TA ≤ +125°C 0.005 0.04 µV/°C

OUTPUT CHARACTERISTICS

Output Voltage High V

OH

R

= 100 kΩ to GND 4.99 4.998 V

L

–40°C to +125°C 4.99 4.997 V

= 10 kΩ to GND 4.95 4.98 V

R

L

–40°C to +125°C 4.95 4.975 V

R

Output Voltage Low V

OL

= 100 kΩ to V+ 1 10 mV

L

–40°C to +125°C210mV

= 10 kΩ to V+ 10 30 mV

R

L

–40°C to +125°C1530mV

Short Circuit Limit I

SC

±25 ±50 mA

–40°C to +125°C ±40 mA

Output Current I

O

±30 mA

–40°C to +125°C ±15 mA

POWER SUPPLY␣

Power Supply Rejection Ratio PSRR V

Supply Current/Amplifier I

SY

= 2.7 V to 5.5 V 120 130 dB

S

–40°C ≤ T

V

= 0 V 850 975 µA

O

≤ +125°C 115 130 dB

A

–40°C ≤ TA ≤ +125°C 1,000 1,075 µA

DYNAMIC PERFORMANCE␣

Slew Rate SR R

= 10 kΩ 0.4 V/µs

L

Overload Recovery Time 0.05 0.3 ms
Gain Bandwidth Product GBP 1.5 MHz

NOISE PERFORMANCE␣

Voltage Noise e

Voltage Noise Density e
Current Noise Density i

NOTE

1

Gain testing is highly dependent upon test bandwidth.

Specifications subject to change without notice.

p–p 0 Hz to 10 Hz 1.3 µV p–p

n

p–p 0 Hz to 1 Hz 0.41 µV p–p

e

n

n

n

f = 1 kHz 51 nV/√Hz
f = 10 Hz 2 fA/√Hz

–2– REV. 0

AD8571/AD8572/AD8574

ELECTRICAL CHARACTERISTICS

(VS = 2.7 V, VCM = 1.35 V, VO = 1.35 V, TA = 25ⴗC unless otherwise noted)

Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS␣

Offset Voltage V

Input Bias Current I

Input Offset Current I

B

OS

OS

–40°C ≤ T
–40°C ≤ T
–40°C ≤ T

≤ +125°C10µV

A

≤ +125°C 1.0 1.5 nA

A

≤ +125°C 150 200 pA

A

15 µV

10 50 pA

10 50 pA

Input Voltage Range 0 2.7 V
Common-Mode Rejection Ratio CMRR V

Large Signal Voltage Gain

1

A

VO

= 0 V to 2.7 V 115 130 dB

CM

–40°C ≤ T

R

= 10 kΩ , V

L

–40°C ≤ T

≤ +125°C 110 130 dB

A

= 0.3 V to 2.4 V 110 140 dB

O

≤ +125°C 105 130 dB

A

Offset Voltage Drift ∆VOS/∆T –40°C ≤ TA ≤ +125°C 0.005 0.04 µV/°C

OUTPUT CHARACTERISTICS

Output Voltage High V

OH

R

= 100 kΩ to GND 2.685 2.697 V

L

–40°C to +125°C 2.685 2.696 V

= 10 kΩ to GND 2.67 2.68 V

R

L

–40°C to +125°C 2.67 2.675 V

R

Output Voltage Low V

OL

= 100 kΩ to V+ 1 10 mV

L

–40°C to +125°C210mV

= 10 kΩ to V+ 10 20 mV

R

L

–40°C to +125°C1520mV

Short Circuit Limit I

SC

±10 ±15 mA

–40°C to +125°C ±10 mA

Output Current I

O

±10 mA

–40°C to +125°C ±5mA

POWER SUPPLY␣

Power Supply Rejection Ratio PSRR V

Supply Current/Amplifier I

SY

= 2.7 V to 5.5 V 120 130 dB

S

–40°C ≤ T

V

= 0 V 750 900 µA

O

≤ +125°C 115 130 dB

A

–40°C ≤ TA ≤ +125°C 950 1,000 µA

DYNAMIC PERFORMANCE␣

Slew Rate SR R

= 10 kΩ 0.5 V/µs

L

Overload Recovery Time 0.05 ms
Gain Bandwidth Product GBP 1 MHz

NOISE PERFORMANCE␣

Voltage Noise e
Voltage Noise Density e
Current Noise Density i

NOTE

1

Gain testing is highly dependent upon test bandwidth.

Specifications subject to change without notice.

p–p 0 Hz to 10 Hz 2.0 µV p–p

n

n

n

f = 1 kHz 94 nV/√Hz
f = 10 Hz 2 fA/√Hz

–3–REV. 0

AD8571/AD8572/AD8574

WARNING!

ESD SENSITIVE DEVICE

ABSOLUTE MAXIMUM RATINGS

Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 V

Input Voltage . . . . . . . . . . . . . . . . . . . . . . GND to V

Differential Input Voltage

2

. . . . . . . . . . . . . . . . . . . . . . ±5.0 V

ESD (Human Body Model) . . . . . . . . . . . . . . . . . . . . . 2,000 V

Output Short-Circuit Duration to GND . . . . . . . . . Indefinite

Storage Temperature Range

RM, RU and R Packages . . . . . . . . . . . . . –65°C to +150°C

Operating Temperature Range

AD8571A/AD8572A/AD8574A . . . . . . . . –40°C to +125°C

Junction Temperature Range

RM, RU and R Packages . . . . . . . . . . . . . –65°C to +150°C

Lead Temperature Range (Soldering, 60 sec) . . . . . . . . 300°C

NOTES

1

Stresses above those listed under Absolute Maximum Ratings may cause perma-

nent damage to the device. This is a stress rating only; functional operation of the
device at these or any other conditions above those listed in the operational sections
of this specification is not implied. Exposure to absolute maximum rating condi­tions for extended periods may affect device reliability.

2

Differential input voltage is limited to ±5.0 V or the supply voltage, whichever is less.

1

+ 0.3 V

S

ORDERING GUIDE

Package Type ␪

1

JA

␪

JC

Unit

8-Lead MSOP (RM) 190 44 °C/W
8-Lead TSSOP (RU) 240 43 °C/W
8-Lead SOIC (R) 158 43 °C/W
14-Lead TSSOP (RU) 180 36 °C/W
14-Lead SOIC (R) 120 36 °C/W

NOTE

1

θJA is specified for worst-case conditions, i.e., θ

for P-DIP packages, θ

SOIC and TSSOP packages.

is specified for device soldered in circuit board for

JA

is specified for device in socket

JA

Temperature Package Package

Model Range Description Option Brand

AD8571ARM

AD8571AR –40°C to +125°C 8-Lead SOIC SO-8

AD8572ARU

AD8572AR –40°C to +125°C 8-Lead SOIC SO-8

AD8574ARU

2

–40°C to +125°C 8-Lead MSOP RM-8 AJA

3

–40°C to +125°C 8-Lead TSSOP RU-8

3

–40°C to +125°C 14-Lead TSSOP RU-14

AD8574AR –40°C to +125°C 14-Lead SOIC SO-14

NOTES

1

Due to package size limitations, these characters represent the part number.

2

Available in reels only. 1,000 or 2,500 pieces per reel.

3

Available in reels only. 2,500 pieces per reel.

CAUTION

ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily
accumulate on the human body and test equipment and can discharge without detection. Although
the AD8571/AD8572/AD8574 features proprietary ESD protection circuitry, permanent damage
may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD
precautions are recommended to avoid performance degradation or loss of functionality.

1

–4– REV. 0

COMMON-MODE VOLTAGE – V

INPUT BIAS CURRENT – pA

1,500

22,000

01

5

234

1,000

500

0

21,000

21,500

2500

VS = 5V
T

A

= 1258C

LOAD CURRENT – mA

10

0.1

0.001

OUTPUT VOLTAGE – mV

0.1

110

1

100

10k

SOURCE

SINK

VS = 5V
T

A

= 258C

100

1k

0.0001 0.01
TEMPERATURE – 8C

SUPPLY CURRENT – mA

1.0

0.8

0

275 250

125

225

0

25 50 75 100

0.6

0.4

0.2

150

5V

2.7V

Typical Performance Characteristics–

AD8571/AD8572/AD8574

180
160

140

120
100

80
60

NUMBER OF AMPLIFIERS

40

20

0

22.5

21.5 20.5

OFFSET VOLTAGE – mV

0.5

VS = 2.7V
VCM = 1.35V
T

= 258C

A

1.5

2.5

Figure 1. Input Offset Voltage
Distribution at 2.7 V

180
160

140

120
100

80
60

NUMBER OF AMPLIFIERS

40

20

0

22.5

21.5 20.5

OFFSET VOLTAGE – mV

VS = 5V
VCM = 2.5V
T

= 258C

A

0.5 2.5

1.5

Figure 4. Input Offset Voltage
Distribution at 5 V

50

VS = 5V

40

T

= 2408C, +258C, +858C

A

30

20

10

0

210

INPUT BIAS CURRENT – pA

220

230

01

INPT MM

234

N-M

DE V

+858C

+258C

2408C

LTA

E – V

Figure 2. Input Bias Current vs.
Common-Mode Voltage

12

VS = 5V

10

8

6

4

NUMBER OF AMPLIFIERS

2

0

01 6

INPUT OFFSET DRIFT – nV/8C

VCM = 2.5V
T

= 2408C TO +1258C

A

234 5

Figure 5. Input Offset Voltage Drift
Distribution at 5 V

5

Figure 3. Input Bias Current vs.
Common-Mode Voltage

Figure 6. Output Voltage to Supply
Rail vs. Output Current at 5 V

10k

1k

100

10

OUTPUT VOLTAGE – mV

1

0.1

0.0001 0.01

Figure 7. Output Voltage to Supply
Rail vs. Output Current at 2.7 V

VS = 2.7V
T

= 258C

A

SOURCE SINK

0.001

0.1

LOAD CURRENT – mA

110

100

1,000

VCM = 2.5V
VS = 5V

750

500

250

INPUT BIAS CURRENT – pA

0

275 250

225

0 25 50 75 100

TEMPERATURE – 8C

125

150

Figure 8. Bias Current vs. Temperature

–5–REV. 0

Figure 9. Supply Current vs.
Temperature

AD8571/AD8572/AD8574

g

g

5ms

1V

VS = +5V
C

L

= 300pF

R

L

= 2kV

AV = 1

800

TA = 258C

700

600

500

400

300

200

100

SUPPLY CURRENT PER AMPLIFIER – mA

0

0

16

2345

SUPPLY VOLTAGE – V

Figure 10. Supply Current vs.
Supply Voltage

60
50
40

AV = 2100

30
20

AV = 210

10

0

AV = +1

210

CLOSED-LOOP GAIN – dB

220
230
240

100 1k 10M10k 100k 1M

FREQUENCY – Hz

VS = 2.7V
CL = 0pF
R

= 2kV

L

Figure 13. Closed Loop Gain vs.
Frequency at 2.7 V

60

VS = 2.7V

50

CL = 0pF
RL =

40
30
20
10

0

210

OPEN-LOOP GAIN – dB

220
230
240

10k 100k 100M1M 10M

FREQUENCY – Hz

Figure 11. Open-Loop Gain and
Phase Shift vs. Frequency at 2.7 V

60
50
40

AV = 2100

30
20

AV = 210

10

0

AV = +1

210

CLOSED-LOOP GAIN – dB

220
230
240

100 1k 10M10k 100k 1M

FREQUENCY – Hz

VS = 5V
CL = 0pF
R

= 2kV

L

Figure 14. Closed Loop Gain vs.
Frequency at 5 V

60

VS = 5V

50

CL = 0pF

0

rees

45
90
135
180
225

PHASE SHIFT – De

270

210

OPEN-LOOP GAIN – dB

220
230
240

RL =

40
30
20
10

0

10k 100k 100M1M 10M

FREQUENCY – Hz

Figure 12. Open-Loop Gain and
Phase Shift vs. Frequency at 5 V

300

VS = 2.7V

270
240
210
180
150
120

90

OUTPUT IMPEDANCE – V

60
30

0

100 1k 10M10k 100k 1M

AV = 100

FREQUENCY – Hz

Figure 15. Output Impedance vs.
Frequency at 2.7 V

AV = 1

AV = 10

0

rees

45
90
135
180
225

PHASE SHIFT – De

270

300

VS = 5V

270
240
210
180
150
120

90

OUTPUT IMPEDANCE – V

60
30

0

100 1k 10M10k 100k 1M

AV = 100

FREQUENCY – Hz

Figure 16. Output Impedance vs.
Frequency at 5 V

AV = 10

AV = 1

VS = 2.7V
CL = 300pF
R

= 2kV

L

AV = 1

2ms

Figure 17. Large Signal Transient
Response at 2.7 V

500mV

Figure 18. Large Signal Transient
Response at 5 V

–6– REV. 0