Datasheet AD8691 Datasheet (Analog Devices)

Low Cost, Low Noise, CMOS Rail-to-Rail

FEATURES

Offset voltage: 400 µV typ
Low offset voltage drift: 6 µV/°C max (AD8692)
Very low input bias currents: 1 pA max
Low noise: 8 nV/√Hz
Low distortion: 0.0006%
Wide bandwidth: 10 MHz
Unity-gain stable
Single-supply operation: 2.7 V to 6 V

APPLICATIONS

Photodiode amplification
Battery-powered instrumentation
Medical instruments
Multipole filters
Sensors
Portable audio devices

Output Operational Amplifiers

AD8691/AD8692

PIN CONFIGURATIONS

OUT

1

AD8691

V–

2

TOP VIEW

(Not to Scale)

3

+IN

Figure 1. 5-Lead TSOT

OUT A

+IN A

AD8691

1

V–

2

3

Figure 2. 5-Lead SC70

OUT A

1

AD8692

2

–IN A
+IN A

V–

TOP VIEW

3

(Not to Scale)

4

Figure 3. 8-Lead MSOP

5

3

5

4

8
7
6
5

V+

–IN

V+

–IN

V+
OUT B
–IN B
+IN B

04991-030

04991-031

04991-001

GENERAL DESCRIPTION

The AD8691 and AD8692 are low cost, single and dual rail-to­rail output, single-supply amplifiers featuring low offset and
input voltages, low current noise, and wide signal bandwidth.
The combination of low offset, low noise, very low input bias
currents, and high speed make these amplifiers useful in a wide
variety of applications. Filters, integrators, photodiode amplifiers,
and high impedance sensors all benefit from this combination
of performance features. Audio and other ac applications
benefit from the wide bandwidth and low distortion of these
devices.

Rev. A

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.

OUT A

–IN A
+IN A

V–

1

AD8692

2
3

TOP VIEW

(Not to Scale)

4

8
7
6
5

V+
OUT B
–IN B
+IN B

04991-002

Figure 4. 8-Lead SOIC

Applications for these amplifiers include PA controls, laser
diode control loops, portable and loop-powered instrumentation,
audio amplification for portable devices, and ASIC input and
output amplifiers.

The small SC70 and TSOT package options for the AD8691
allow it to be placed next to sensors, thereby reducing external
noise pickup.

The AD8691 and AD8692 are specified over the extended
industrial temperature range of −40°C to +125°C. The AD8691
is available in 5-lead SC70 and TSOT packages. The AD8692 is
available in 8-lead MSOP and narrow SOIC surface-mount
packages.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone]
Fax: [phone] © 2005 Analog Devices, Inc. All rights reserved.

www.analog.com

AD8691/AD8692

TABLE OF CONTENTS

Electrical Characteristics................................................................. 3

Typical Perfor m a n c e C haracter i s t ic s ..............................................6

Absolute Maximum Ratings............................................................ 5

Thermal Characteristics .............................................................. 5

ESD Caution.................................................................................. 5

REVISION HISTORY

1/05 — Rev. 0 to Rev. A

Added AD8691 ...................................................................Universal

Changes to Features.......................................................................... 1

Added Figure 1 and Figure 2........................................................... 1

Changes to Electrical Characteristics ............................................ 3

Changes to Figure 6 caption............................................................ 6

Changes to Figure 9.......................................................................... 6

Updated Outline Dimensions....................................................... 11

Changes to Ordering Guide.......................................................... 11

10/04—Revision 0: Initial Version

Outline Dimensions ....................................................................... 11

Ordering Guide .......................................................................... 12

Rev. A | Page 2 of 12

AD8691/AD8692

ELECTRICAL CHARACTERISTICS

VS = 2.7 V, VCM = VS/2, TA = 25°C, unless otherwise noted.

Table 1.

Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS

Offset Voltage V

OS

V
Input Bias Current I

B

−40°C < TA < +85°C 50 pA

−40°C < TA < +125°C 260 pA
Input Offset Current I

OS

−40°C < TA < +85°C 20 pA

−40°C < TA < +125°C 75 pA
Input Voltage Range −0.3 +1.6 V
Common-Mode Rejection Ratio CMRR VCM = −0.3 V to +1.6 V 70 90 dB
V
Large Signal Voltage Gain A

VO

Offset Voltage Drift ∆VOS/∆T

AD8691 2 12 µV/°C
AD8692 1.3 6 µV/°C

OUTPUT CHARACTERISTICS

Output Voltage High V

OH

−40°C < TA < +125°C 2.6 V
Output Voltage Low V

OL

−40°C < TA < +125°C 50 mV
Short-Circuit Current I
Closed-Loop Output Impedance Z

SC

OUT

POWER SUPPLY

Power-Supply Rejection Ratio PSRR VS = 2.7 V to 5.5 V 80 95 dB

−40°C < TA < +125°C 75 95 dB
Supply Current/Amplifier I

SY

−40°C < TA < +125°C 1.2 mA

DYNAMIC PERFORMANCE

Slew Rate SR RL = 2 kΩ 5 V/µs
Settling Time t

S

Gain Bandwidth Product GBP 10 MHz
Phase Margin Øo 60 Degrees
Total Harmonic Distortion + Noise THD + N

NOISE PERFORMANCE

Voltage Noise e
Voltage Noise Density e
e
Current Noise Density i

n p-p

n

n

n

VCM = −0.3 V to +1.6 V 0.4 2.0 mV

= −0.1 V to +1.6 V; −40°C < TA < +125°C 3.0 mV

CM

0.2 1 pA

0.1 0.5 pA

= −0.1 V to +1.6 V; −40°C < TA < +125°C 65 85 dB

CM

RL = 2 kΩ, VO = 0.5 V to 2.2 V 90 250 V/mV

IL = 1 mA 2.64 2.66 V

IL = 1 mA 25 40 mV

±20 mA
f = 1 MHz, AV = 1 12 Ω

VO = 0 V 0.85 0.95 mA

To 0.01% 1 µs

G = 1, R

= 600 Ω, f = 1 kHz, VO = 250 mV p-p

L

0.003 %

f = 0.1 Hz to 10 Hz 1.6 3.0 µV p-p
f = 1 kHz 8 12 nV/√Hz
f = 10 kHz 6.5 nV/√Hz
f = 1 kHz 0.05 pA/√Hz

Rev. A | Page 3 of 12

AD8691/AD8692

VS = 5.0 V, VCM = VS/2, TA = 5°C, unless otherwise noted.

Table 2.

A Grade
Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS

Offset Voltage V

OS

V
Input Bias Current I

B

−40°C < TA < +85°C 50 pA

−40°C < TA < +125°C 260 pA
Input Offset Current I

OS

−40°C < TA < +85°C 20 pA

−40°C < TA < +125°C 75 pA
Input Voltage Range

Common-Mode Rejection Ratio CMRR VCM = −0.3 V to +3.9 V 75 95 dB
V
Large Signal Voltage Gain A
Offset Voltage Drift

∆V

VO

OS

AD8691 2 12 µV/°C
AD8692 1.3 6 µV/°C

OUTPUT CHARACTERISTICS

Output Voltage High V

OH

I

−40°C to +125°C 4.6 V
Voltage Low V

OL

I

−40°C to +125°C 290 mV
Short-Circuit Current I
Closed-Loop Output Impedance Z

SC

OUT

POWER SUPPLY

Power Supply Rejection Ratio PSRR VS = 2.7 V to 5.5 V 80 95 dB

−40°C < TA < +125°C 75 95 dB
Supply Current/Amplifier I

SY

−40°C < TA < +125°C 1.3 mA

DYNAMIC PERFORMANCE

Slew Rate SR RL = 2 kΩ 5 V/µs
Settling Time t
Full Power Bandwidth BW

S

P

Gain Bandwidth Product GBP 10 MHz
Phase Margin Øo 65 Degrees
Total Harmonic Distortion + Noise THD + N

NOISE PERFORMANCE

Voltage Noise e
Voltage Noise Density e
e
Current Noise Density i

n p-p

n

n

n

VCM = −0.3 V to +3.9 V 0.4 2.0 mV

= −0.1 V to +3.9 V; −40°C < TA < +125°C 3.0 mV

CM

0.2 1 pA

0.1 0.5 pA

+3.9 V

−0.3

= −0.1 V to +3.9 V; −40°C < TA < +125°C 70 95 dB

CM

VO = 0.5 V to 4.5 V, RL = 2 kΩ, VCM = 0 V 250 2000 V/mV

/∆T

IL = 1 mA 4.96 4.98 V

= 10 mA 4.7 4.78 V

L

IL = 1 mA 16.5 40 mV

= 10 mA 165 210 mV

L

±80 mA
f = 1 MHz, AV = 1 10 Ω

VO = 0 V 0.95 1.05 mA

To 0.01% 1 µs
<1% distortion 360 kHz

G = 1, R

= 600 Ω, f = 1 kHz, VO = 1 V p-p

L

0.0006 %

f = 0.1 Hz to 10 Hz 1.6 3.0 µV p-p
f = 1 kHz 8 12
f = 10 kHz 6.5
f = 1 kHz 0.05

nV/√Hz
nV/√Hz
pA/√Hz

Rev. A | Page 4 of 12

AD8691/AD8692

ABSOLUTE MAXIMUM RATINGS

TA = 25°C, unless otherwise noted.

Table 3.

Parameters Ratings

Supply Voltage 6 V
Input Voltage VSS − 0.3 V to VDD + 0.3 V
Differential Input Voltage ±6 V
Output Short-Circuit Duration

to GND Observe derating curves
Storage Temperature Range −65°C to +150°C
Operating Temperature Range −40°C to +125°C
Junction Temperature Range −65°C to +150°C
Lead Temperature Range

(Soldering, 60 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 CHARACTERISTICS

Table 4.

Package Type θ

8-Lead MSOP (RM) 210 45 °C/W
8-Lead SOIC (R) 158 43 °C/W
5-Lead TSOT (UJ-5) 207 61 °C/W
5-Lead SC70 (KS) 376 126 °C/W

1

θJA is specified for the worst-case conditions, that is, the device soldered in

the circuit board for surface-mount packages.

1

JA

θ

Unit

JC

ESD 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 this product 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.

Rev. A | Page 5 of 12

AD8691/AD8692

TYPICAL PERFORMANCE CHARACTERISTICS

VS = +5 V or ±2.5 V, unless otherwise noted.

2.5k
VS = 5V

V

= –0.3V TO +3.9V

CM

2.0k

1.5k

1.0k

NUMBER OF AMPLIFIERS

500

0
–2.0 –1.5 –1.0 –0.5 0 0.5 1.0 1.5 2.0

VOS (mV)

Figure 5. Input Offset Voltage Distribution

30

VS = 5V AND 2.7V
V

= 2.5V

25

20

15

10

NUMBER OF AMPLIFIERS

5

CM

T

= –40°C TO +125°C

A

04991-003

300

VS = 5V AND 2.7V

250

200

150

IB (pA)

IB (pA)

100

50

0

–50

–40 –20 0 20 40 60 80 100 120

–10 10 30 50 70 90 110

–30

TEMPERATURE (°C)

Figure 8. Input Bias Current vs. Temperature

1.0

0.8

0.6

(mA)

SY

I

0.4

0.2

04991-006

0

4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.00 0.5 1.0 1.5 2.0 2.5 3.0 3.5

TCVOS (µV/°C)

Figure 6. AD8692 Input Offset Voltage Drift Distribution

2.0k
VS = 5V

1.6k

T

= 25°C

A

1.2k

800

400

0

–400

–800

INPUT OFFSET VOLTAGE (µV)

–1.2k

–1.6k

–2.0k

–0.3 0 0.3 0.6 0.9 1.2 1.8 3.01.5 2.1 2.4 2.7 3.63.3 3.9

COMMON-MODE VOLTAGE (V)

Figure 7. Input Offset Voltage vs. Common-Mode Voltage

04991-004

04991-005

Rev. A | Page 6 of 12

0

01234567

V

(V)

SY

Figure 9. Supply Current vs. Supply Voltage

2.5
VS =±2.5V AND±1.35V

2.0

1.5

1.0

SUPPLY CURRENT (mA)

0.5

0

–40 –20 0 20 40 60 80 100 120 140

TEMPERATURE (

@±2.5V

I

SY

ISY @±1.35V

°

C)

Figure 10. Supply Current vs. Temperature

04991-007

04991-008

AD8691/AD8692

10k

100

1k

SOURCE

SINK

100

VSY = ±2.5V, ±1.35V
R

= 2kΩ

L

C

= 15pF

80

60

40

L

90

10

1

OUTPUT VOLTAGE TO SUPPLY RAIL (mV)

0.1

0.001 0.01 0.1 1 10 100
LOAD CURRENT (mA)

Figure 11. Output Voltage to Supply Rail vs. Load Current

35

VS = 5V

30

25

20

15

10

OUTPUT VOLTAGE SWING (mV)

5

0

–40 –20 0 20 40 60 80 100 120 140

VDD– VOH @ 1mA

TEMPERATURE (

V

@ 1mA

OL

°

C)

Figure 12. Output Voltage Swing vs. Temperature (I

= 1 mA)

L

04991-009

04991-010

20

OPEN-LOOP GAIN (dB)

0

–20

–40

1k 10k 100k 1M 10M

FREQUENCY (Hz)

Figure 14. Open-Loop Gain and Phase vs. Frequency

120

100

80

60

CMRR (dB)

40

20

0

1k 10k 100k 1M 10M

FREQUENCY (Hz)

VS = 5V AND 2.7V

Figure 15. CMRR vs. Fre quency

45

0

–45

–90

PHASE (Degrees)

04991-012

04991-013

350

VS = 5V

300

– VOH @ 10mA

V

250

200

150

100

OUTPUT VOLTAGE SWING (mV)

50

0

–40 –20 0 20 40 60 80 100 120 140

DD

TEMPERATURE (

V

OL

@ 10mA

°

C)

Figure 13. Output Voltage Swing vs. Temperature (I

= 10 mA)

L

04991-011

Rev. A | Page 7 of 12

120

100

80

60

PSRR (dB)

40

20

0

10 100 1k 10k 100k 1M 10M

FREQUENCY (Hz)

VS = 5V AND 2.7V

Figure 16. PSRR v s. Frequency

04991-014

AD8691/AD8692

10k

1k

A

= 100

100

10

1

0.1

IMPEDANCE (Ω)

0.01

0.001

0.0001
100 1k 10k 100k 1M 10M

V

FREQUENCY (Hz)

A

= 10

V

A

= 1

V

Figure 17. Closed-Loop Output Impedance vs. Frequency

40

VS = 5V AND 2.7V

=

∞

R

35

L

AV = 1

30

25

20

VS = ±2.5V

04991-015

VOLTAGE (1V/DIV)

(V)

V

OUT

–2.5

VS = 5V

= 200pF

C

L

R

= ∞

L

= 1

A

V

TIME (400ns/DIV)

04991-018

Figure 20. Large Signal Transient Response

VS = ±2.5V
A

= –50

V

0

15

OVERSHOOT (%)

10

5

0

1 10 100 1k

LOAD CAPACITANCE (pF)

Figure 18. Small Signal Overshoot vs. Load Capacitance

VS = ±2.5V, ±1.35V

= 10kΩ

R

L

= 200pF

C

L

= 1

A

V

VOLTAGE (50mV/DIV)

TIME (200ns/DIV)

Figure 19. Small Signal Transient Response

04991-016

04991-017

(mV)
V

(V)

V

(mV)
V

IN

OUT

IN

100

–100

2.5

0

TIME (400ns/DIV)

04991-019

Figure 21. Positive Overload Recovery

VS = ±2.5V
A

= –50

V

0

0

TIME (400ns/DIV)

04991-020

Figure 22. Negative Overload Recovery

Rev. A | Page 8 of 12

AD8691/AD8692

0.1
VS = ±2.5V
A

= 1

V

= 1V p-p

V

IN

BW = 20kHz

1k

VS = ±2.5V AND ±1.35V

0.01

R

= 600Ω

L

THD + N (%)

0.001

0.0001
20 100 1k 10k 20k

= 1kΩ

R

L

FREQUENCY (Hz)

= 100kΩ

R

L

Figure 23. THD + N vs. Frequency

VS = 5V AND 2.7V

VOLTAGE NOISE (1µV/DIV)

04991-021

100

NOISE (nV/ Hz)

10

1

101 100 1k 10k

Figure 25. Voltage Noise Density

150

140

130

120

110

100

CHANNEL SEPARATION (dB)

90

28mV p-p

FREQUENCY (Hz)

+2.5V

V+

V

A

IN

V–

–2.5V

04991-023

R1

10kΩ

R2

100Ω

V–

B

V

OUT

V+

80

1k 10k 100k 1M 10M

TIME (1s/DIV)

Figure 24. 0.1 Hz to 10 Hz Input Voltage Noise

04991-022

FREQUENCY (Hz)

Figure 26. AD8692 Channel Separation

04991-024

Rev. A | Page 9 of 12

AD8691/AD8692

VS = +2.7 V or ±1.35 V, unless otherwise noted.

1.2k
VS = 2.7V
VCM = –0.3V TO +1.6V

1.0k

800

60

50

40

VS = 2.7V

VDD– VOH @ 1mA

600

400

NUMBER OF AMPLIFIERS

200

0

–2.0 –1.5 –1.0 –0.5 0 0.5 1.0 1.5 2.0

VOS (mV)

Figure 27. Input Offset Voltage Distribution

2.0k

VS = 2.7V

1.6k

= 25°C

T

A

1.2k

800

400

0

–400

–800

INPUT OFFSET VOLTAGE (µV)

–1.2k

–1.6k

–2.0k

–0.3 0 0.3 0.6 0.9 1.2 1.5 1.6

COMMON-MODE VOLTAGE (V)

Figure 28. Input Offset Voltage vs. Common-Mode Voltage

04991-025

04991-026

30

20

OUTPUT VOLTAGE SWING (mV)

10

0

–40 –20 0 20 40 60 80 100 120 140

TEMPERATURE (°C)

V

@ 1mA

OL

Figure 30. Output Voltage Swing vs. Temperature

VS = 2.7V
C
R
A

VOLTAGE (500mV/DIV)

TIME (400ns/DIV)

Figure 31. Large Signal Transient Response

= 200pF

L

= ∞

L

= 1

V

04991-028

04991-029

10k

V

= 2.7V

S

1k

100

10

1

OUTPUT VOLTAGE TO SUPPLY RAIL (mV)

0.1

0.001 0.01 0.1 1 10 100
LOAD CURRENT (mA)

SOURCE

SINK

Figure 29. Output Voltage to Supply Rail vs. Load Current

04991-027

Rev. A | Page 10 of 12

AD8691/AD8692

OUTLINE DIMENSIONS

3.00
BSC

85

3.00
BSC

PIN 1

0.65 BSC

0.15

0.00

0.38

0.22

COPLANARITY

0.10
COMPLIANT TO JEDEC STANDARDS MO-187AA

4

SEATING
PLANE

4.90
BSC

1.10 MAX

0.23

0.08

8°
0°

Figure 32. 8-Lead Mini Small Outline Package [MSOP]

(RM-8)

Dimensions shown in millimeters

0.80

0.60

0.40

4.00 (0.1574)

3.80 (0.1497)

0.25 (0.0098)

0.10 (0.0040)

COPLANARITY

0.10

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

5.00 (0.1968)

4.80 (0.1890)

85

1.27 (0.0500)

SEATING

PLANE

COMPLIANT TO JEDEC STANDARDS MS-012AA

BSC

6.20 (0.2440)

5.80 (0.2284)

41

1.75 (0.0688)

1.35 (0.0532)

0.51 (0.0201)

0.31 (0.0122)

0.25 (0.0098)

0.17 (0.0067)

0.50 (0.0196)

0.25 (0.0099)

8°

1.27 (0.0500)

0°

0.40 (0.0157)

Figure 34. 8-Lead Standard Small Outline Package [SOIC]

Narrow Body (R-8)

Dimensions shown in millimeters and (inches)

2.90 BSC

× 45°

2.20

2.00

1.80

1.35

1.25

1.15

1.00

0.90

0.70

.

0

0

1

M

123

PIN 1

X

A

0.30

0.15

0.10 COPLANARITY

COMPLIANT TO JEDEC STANDARDS MO-203AA

45

0.65 BSC

2.40

2.10

1.80

1.10

0.80

SEATING
PLANE

0.40

0.10

0.22

0.08

Figure 33. 5-Lead Thin Shrink Small Outline Package [SC70]

(KS-5)

Dimensions shown in millimeters

0.30

0.10

54

0.50

0.30

2.80 BSC

0.95 BSC

*

1.00 MAX

SEATING
PLANE

0.20

0.08
8°

4°
0°

0.60

0.45

0.30

1.60 BSC

123

PIN 1

*

0.90

0.87

0.84

0.10 MAX

*

COMPLIANT TO JEDEC STANDARDS MO-193-AB WITH
THE EXCEPTION OF PACKAGE HEIGHT AND THICKNESS.

1.90
BSC

Figure 35. 5-Lead Thin Small Outline Transistor Package [TSOT ]

(UJ-5)

Dimensions shown in millimeters

Rev. A | Page 11 of 12

AD8691/AD8692

ORDERING GUIDE

Model Temperature Range Package Description Package Option Branding

AD8691AUJZ-R21 −40°C to +125°C 5-Lead TSOT UJ-5 ACA
AD8691AUJZ-REEL1 −40°C to +125°C 5-Lead TSOT UJ-5 ACA
AD8691AUJZ-REEL71 −40°C to +125°C 5-Lead TSOT UJ-5 ACA
AD8691AKSZ-R21 −40°C to +125°C 5-Lead SC70 KS-5 ACA
AD8691AKSZ-REEL1 −40°C to +125°C 5-Lead SC70 KS-5 ACA
AD8691AKSZ-REEL71 −40°C to +125°C 5-Lead SC70 KS-5 ACA
AD8692ARMZ-R2
AD8692ARMZ-REEL1 −40°C to +125°C 8-Lead MSOP RM-8 APA
AD8692ARZ1 −40°C to +125°C 8-Lead SOIC R-8
AD8692ARZ-REEL1 −40°C to +125°C 8-Lead SOIC R-8
AD8692ARZ-REEL71 −40°C to +125°C 8-Lead SOIC R-8

1

Z = Pb-free part.

1

−40°C to +125°C 8-Lead MSOP RM-8 APA

© 2005 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.

D04991-0-1/05(A)

Rev. A | Page 12 of 12