ANALOG DEVICES AD8610, AD8620 Service Manual

Precision, Very Low Noise,

Low Input Bias Current, Wide Bandwidth

JFET Operational Amplifier

AD8610/AD8620

FEATURES
Low Noise 6 nV/

√

Hz

Low Offset Voltage: 100 ␮V Max
Low Input Bias Current 10 pA Max
Fast Settling: 600 ns to 0.01%
Low Distortion
Unity Gain Stable
No Phase Reversal
Dual-Supply Operation: ⴞ5 V to ⴞ13 V

APPLICATIONS
Photodiode Amplifier
ATE
Instrumentation
Sensors and Controls
High Performance Filters
Fast Precision Integrators
High Performance Audio

GENERAL DESCRIPTION

The AD8610/AD8620 is a very high precision JFET input amplifier
featuring ultralow offset voltage and drift, very low input voltage
and current noise, very low input bias current, and wide bandwidth.
Unlike many JFET amplifiers, the AD8610/AD8620 input bias
current is low over the entire operating temperature range. The
AD8610/AD8620 is stable with capacitive loads of over 1000 pF
in noninverting unity gain; much larger capacitive loads can be
driven easily at higher noise gains. The AD8610/AD8620 swings to
within 1.2 V of the supplies even with a 1 kΩ load, maximizing
dynamic range even with limited supply voltages. Outputs slew at
50 V/µs in either inverting or noninverting gain configurations, and
settle to 0.01% accuracy in less than 600 ns. Combined with the
high input impedance, great precision, and very high output drive, the

FUNCTIONAL BLOCK DIAGRAMS

8-Lead MSOP and SOIC
(RM-8 and R-8 Suffixes)

1

NULL

ⴚIN
ⴙIN

Vⴚ

NC = NO CONNECT

8

AD8610

45

NC
Vⴙ
OUT
NULL

8-Lead SOIC

(R-8 Suffix)

1

OUTA

ⴚINA
ⴙINA

Vⴚ

8

AD8620

45

Vⴙ
OUTB

ⴚINB
ⴙINB

AD8610/AD8620 is an ideal amplifier for driving high performance
A/D inputs and buffering D/A converter outputs.

Applications for the AD8610/AD8620 include electronic instru­ments; ATE amplification, buffering, and integrator circuits;
CAT/MRI/ultrasound medical instrumentation; instrumentation
quality photodiode amplification; fast precision filters (including
PLL filters); and high quality audio.

The AD8610/AD8620 is fully specified over the extended
industrial (–40°C to +125°C) temperature range. The AD8610
is available in the narrow 8-lead SOIC and the tiny MSOP8
surface-mount packages. The AD8620 is available in the narrow
8-lead SOIC package. MSOP8 packaged devices are available
only in tape and reel.

REV. D

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. 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.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] www.analog.com
Fax: [phone] © 2004 Analog Devices, Inc. All rights reserved.

AD8610/AD8620–SPECIFICATIONS

(@ VS = ⴞ5.0 V, VCM = 0 V, TA = 25ⴗC, unless otherwise noted.)

Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS

Offset Voltage (AD8610B) V

Offset Voltage (AD8620B) V

Offset Voltage (AD8610A/AD8620A) V

Input Bias Current I

Input Offset Current I

B

OS

OS

OS

OS

–40°C < T

–40°C < T

+25°C < T
–40°C < T

–40°C < T
–40°C < T

–40°C < T
–40°C < T

< +125°C80200 µV

A

< +125°C80300 µV

A

< 125°C90350 µV

A

< +125°C 150 850 µV

A

–10 +2 +10 pA

< +85°C –250 +130 +250 pA

A

< +125°C –2.5 +1.5 +2.5 nA

A

–10 +1 +10 pA

< +85°C –75 +20 +75 pA

A

< +125°C –150 +40 +150 pA

A

45 100 µV

45 150 µV

85 250 µV

Input Voltage Range –2 +3 V
Common-Mode Rejection Ratio CMRR V
Large Signal Voltage Gain A
Offset Voltage Drift (AD8610B) ∆V
Offset Voltage Drift (AD8620B) ∆V

VO

/∆T –40°C < TA < +125°C 0.5 1 µV/°C

OS

/∆T –40°C < TA < +125°C 0.5 1.5 µV/°C

OS

= –2.5 V to +1.5 V 90 95 dB

CM

RL = 1 kΩ, VO = –3 V to +3 V 100 180 V/mV

Offset Voltage Drift (AD8610A/AD8620A) ∆VOS/∆T –40°C < TA < +125°C 0.8 3.5 µV/°C

OUTPUT CHARACTERISTICS

Output Voltage High V
Output Voltage Low V
Output Current I

OH

OL

OUT

RL = 1 kΩ, –40°C < TA < +125°C 3.8 4 V
RL = 1 kΩ, –40°C < TA < +125°C–4–3.8 V
V

> ±2 V ± 30 mA

OUT

POWER SUPPLY

Power Supply Rejection Ratio PSRR VS = ±5 V to ±13 V 100 110 dB
Supply Current/Amplifier I

SY

VO = 0 V 2.5 3.0 mA
–40°C < TA < +125°C 3.0 3.5 mA

DYNAMIC PERFORMANCE

Slew Rate SR RL = 2 kΩ 40 50 V/µs
Gain Bandwidth Product GBP 25 MHz
Settling Time t

S

AV = +1, 4 V Step, to 0.01% 350 ns

NOISE PERFORMANCE

Voltage Noise en p-p 0.1 Hz to 10 Hz 1.8 µV p-p
Voltage Noise Density e
Current Noise Density i
Input Capacitance C

n

n

IN

f = 1 kHz 6 nV/√Hz
f = 1 kHz 5 fA/√Hz

Differential 8pF
Common-Mode 15 pF

Channel Separation C

S

f = 10 kHz 137 dB
f = 300 kHz 120 dB

Specifications subject to change without notice.

REV. D–2–

AD8610/AD8620

ELECTRICAL SPECIFICATIONS

(@ VS = ⴞ13 V, VCM = 0 V, TA = 25ⴗC, unless otherwise noted.)

Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS

Offset Voltage (AD8610B) V

OS

45 100 µV

–40°C < TA < +125°C80200 µV

Offset Voltage (AD8620B) V

Offset Voltage (AD8610A/AD8620A) V

Input Bias Current I

OS

–40°C < T

OS

+25°C < T
–40°C < T

B

–40°C < T

< +125°C80300 µV

A

< 125°C90350 µV

A

< +125°C 150 850 µV

A

–10 +3 +10 pA

< +85°C –250 +130 +250 pA

A

45 150 µV

85 250 µV

–40°C < TA < +125°C –3.5 +3.5 nA

Input Offset Current I

OS

–40°C < T

< +85°C –75 +20 +75 pA

A

–10 +1.5 +10 pA

–40°C < TA < +125°C –150 +40 +150 pA

Input Voltage Range –10.5 +10.5 V
Common-Mode Rejection Ratio CMRR V
Large Signal Voltage Gain A
Offset Voltage Drift (AD8610B) ∆V
Offset Voltage Drift (AD8620B) ∆V

VO

/∆T –40°C < TA < +125°C 0.5 1 µV/°C

OS

/∆T –40°C < TA < +125°C 0.5 1.5 µV/°C

OS

= –10 V to +10 V 90 110 dB

CM

RL = 1 kΩ, VO = –10 V to +10 V 100 200 V/mV

Offset Voltage Drift (AD8610A/AD8620A) ∆VOS/∆T –40°C < TA < +125°C 0.8 3.5 µV/°C

OUTPUT CHARACTERISTICS

Output Voltage High V
Output Voltage Low V
Output Current I
Short Circuit Current I

OH

OL

OUT

SC

RL = 1 kΩ, –40°C < TA < +125°C +11.75 +11.84 V
RL = 1 kΩ, –40°C < TA < +125°C –11.84 –11.75 V
V

> 10 V ±45 mA

OUT

±65 mA

POWER SUPPLY

Power Supply Rejection Ratio PSRR VS = ±5 V to ±13 V 100 110 dB
Supply Current/Amplifier I

SY

VO = 0 V 3.0 3.5 mA
–40°C < TA < +125°C 3.5 4.0 mA

DYNAMIC PERFORMANCE

Slew Rate SR RL = 2 kΩ 40 60 V/µs
Gain Bandwidth Product GBP 25 MHz
Settling Time t

S

AV = 1, 10 V Step, to 0.01% 600 ns

NOISE PERFORMANCE

Voltage Noise en p-p 0.1 Hz to 10 Hz 1.8 µV p-p
Voltage Noise Density e
Current Noise Density i
Input Capacitance C

n

n

IN

f = 1 kHz 6 nV/√Hz
f = 1 kHz 5 fA/√Hz

Differential 8pF
Common-Mode 15 pF

Channel Separation C

S

f = 10 kHz 137 dB
f = 300 kHz 120 dB

Specifications subject to change without notice.

REV. D

–3–

AD8610/AD8620

ABSOLUTE MAXIMUM RATINGS*

Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27.3 V

Input Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . V

S––

to V

S+

Differential Input Voltage . . . . . . . . . . . . . . . ± Supply Voltage

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

Storage Temperature Range

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

Operating Temperature Range

AD8610/AD8620 . . . . . . . . . . . . . . . . . . . .–40°C to +125°C

Junction Temperature Range

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

Lead Temperature Range (Soldering, 10 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 listed in the operational sections of this
specification is not implied. Exposure to absolute maximum rating conditions for
extended periods may affect device reliability.

ORDERING GUIDE

Temperature Package Package

Model Range Description Option Branding

AD8610AR –40°C to +125°C 8-Lead SOIC RN-8
AD8610AR-REEL –40°C to +125°C 8-Lead SOIC RN-8
AD8610AR-REEL7 –40°C to +125°C 8-Lead SOIC RN-8
AD8610ARM-REEL –40°C to +125°C 8-Lead MSOP RM-8 B0A
AD8610ARM-R2 –40°C to +125°C 8-Lead MSOP RM-8 B0A
AD8610ARZ* –40°C to +125°C 8-Lead SOIC RN-8
AD8610ARZ-REEL* –40°C to +125°C 8-Lead SOIC RN-8
AD8610ARZ-REEL7* –40°C to +125°C 8-Lead SOIC RN-8
AD8610BR –40°C to +125°C 8-Lead SOIC RN-8
AD8610BR-REEL –40°C to +125°C 8-Lead SOIC RN-8
AD8610BR-REEL7 –40°C to +125°C 8-Lead SOIC RN-8
AD8610BRZ* –40°C to +125°C 8-Lead SOIC RN-8
AD8610BRZ-REEL* –40°C to +125°C 8-Lead SOIC RN-8
AD8610BRZ-REEL7* –40°C to +125°C 8-Lead SOIC RN-8
AD8620AR –40°C to +125°C 8-Lead SOIC RN-8
AD8620AR-REEL –40°C to +125°C 8-Lead SOIC RN-8
AD8620AR-REEL7 –40°C to +125°C 8-Lead SOIC RN-8
AD8620BR –40°C to +125°C 8-Lead SOIC RN-8
AD8620BR-REEL –40°C to +125°C 8-Lead SOIC RN-8
AD8620BR-REEL7 –40°C to +125°C 8-Lead SOIC RN-8

Package Type ␪JA* ␪

JC

Unit

8-Lead MSOP (RM) 190 44 °C/W
8-Lead SOIC (RN) 158 43 °C/W

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

soldered in circuit board for surface-mount packages.

is specified for a device

JA

*Pb-free part

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
AD8610/AD8620 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. D–4–

Typical Performance Characteristics–AD8610/AD8620

14

12

10

8

6

4

NUMBER OF AMPLIFIERS

2

0

ⴚ150

ⴚ250

ⴚ50

INPUT OFFSET VOLTAGE – ␮V

VS = ⴞ13V

50 150

250

TPC 1. Input Offset Voltage at±13 V

600

400

200

0

–200

–400

INPUT OFFSET VOLTAGE – ␮V

–600

–40 25 85 125

TEMPERATURE – ⴗC

V

S

= ⴞ5V

600

VS = ⴞ13V

400

200

0

ⴚ200

ⴚ400

INPUT OFFSET VOLTAGE – ␮V

ⴚ600

ⴚ40

25 85 125

TEMPERATURE – ⴗC

TPC 2. Input Offset Voltage vs.
Temperature at±13 V (300 Amplifiers)

14

12

10

8

6

4

NUMBER OF AMPLIFIERS

2

0

00.2 0.6 1.0 1.4 1.8 2.2 2.6

VS = ⴞ5V OR ⴞ13V

TCVOS – ␮V/ⴗC

18

16

14

12

10

8

6

4

NUMBER OF AMPLIFIERS

2

0

ⴚ150

ⴚ250

ⴚ50

INPUT OFFSET VOLTAGE – ␮V

VS = ⴞ5V

50 150

250

TPC 3. Input Offset Voltage at±5 V

3.6

3.4

3.2

3.0

2.8

2.6

2.4

INPUT BIAS CURRENT – pA

2.2

2.0
ⴚ10 ⴚ5

COMMON-MODE VOLTAGE – V

0510

VS = ⴞ13V

TPC 4. Input Offset Voltage vs.
Temperature at±5 V (300 Amplifiers)

3.0

2.5

2.0

1.5

1.0

SUPPLY CURRENT – mA

0.5

0

013123456789101112

SUPPLY VOLTAGE – ⴞV

TPC 7. Supply Current vs.
Supply Voltage

TPC 5. Input Offset Voltage Drift

3.05

2.95

2.85

2.75

SUPPLY CURRENT – mA

2.65

2.55
ⴚ40

25 85 125

TEMPERATURE – ⴗC

VS = ⴞ13V

TPC 8. Supply Current vs.
Temperature at±13 V

TPC 6. Input Bias Current vs.
Common-Mode Voltage

2.65
VS = ⴞ5V

2.60

2.55

2.50

2.45

2.40

SUPPLY CURRENT – mA

2.35

2.30

ⴚ40

25 85 125

TEMPERATURE – ⴗC

TPC 9. Supply Current vs.

±

Temperature at

5 V

REV. D

–5–

AD8610/AD8620

1.8

1.6

1.4

1.2

1.0

0.8

0.6

0.4

0.2

OUTPUT VOLTAGE TO SUPPLY RAIL– V

0

RESISTANCE LOAD – ⍀

TPC 10. Output Voltage to
Supply Rail vs. Load

12.05
VS = ⴞ13V

= 1k⍀

R

L

12.00

11.95

11.90

11.85

OUTPUT VOLTAGE HIGH – V

11.80

ⴚ40

25 85 125

TEMPERATURE – ⴗC

TPC 13. Output Voltage High

±

vs. Temperature at

13 V

VS = ⴞ13V

4.25
VS = ⴞ5V

= 1k⍀

R

L

4.20

4.15

4.10

4.05

OUTPUT VOLTAGE HIGH – V

4.00

100M10M1M100k10k1k100

3.95

ⴚ40

25 85 125

TEMPERATURE – ⴗC

TPC 11. Output Voltage High vs.

±

Temperature at

ⴚ11.80

ⴚ11.85

ⴚ11.90

ⴚ11.95

OUTPUT VOLTAGE LOW – V

ⴚ12.00

ⴚ12.05

ⴚ40

5 V

25 85 125

TEMPERATURE – ⴗC

VS = ⴞ13V

= 1k⍀

R

L

TPC 14. Output Voltage Low vs.
Temperature at±13 V

OUTPUT VOLTAGE LOW – V

ⴚ3.95

ⴚ4.00

ⴚ4.05

ⴚ4.10

ⴚ4.15

ⴚ4.20

ⴚ4.25

ⴚ4.30

ⴚ40

25 85 125

TEMPERATURE – ⴗC

VS = ⴞ5V
RL = 1k⍀

TPC 12. Output Voltage Low vs.

±

Temperature at

120

VS = ⴞ13V

100

R

= 1k⍀

L

MARKER AT 27MHz

80

␪

= 69.5

M

C

= 20pF

L

60

40

20

0

GAIN – dB

ⴚ20

ⴚ40

ⴚ60

ⴚ80

1

FREQUENCY – MHz

5 V

10

TPC 15. Open-Loop Gain
and Phase vs. Frequency

270

225

180

135

90

45

0

ⴚ45

ⴚ90

ⴚ135

ⴚ180

200100

PHASE – Degrees

60

40

G = 100

20

G = 10

0

G = 1

CLOSED-LOOP GAIN – dB

ⴚ20

ⴚ40

10k 100k 1M1k 10M 100M

FREQUENCY – Hz

V

S

RL = 2k⍀
C

L

TPC 16. Closed-Loop Gain vs.
Frequency

= ⴞ13V

= 20pF

260

240

220

200

180

– V/mV

VO

A

160

140

120

100

ⴚ40

25 85 125

TEMPERATURE – ⴗC

= ⴞ13V

V

S

= ⴞ10V

V

O

= 1k⍀

R

L

TPC 17. AVO vs. Temperature at±13 V

190

180

170

160

150

– V/mV

140

VO

A

130

120

110

100

ⴚ40

25 85 125

TEMPERATURE – ⴗC

VS = ⴞ5V

= ⴞ3V

V

O

RL = 1k⍀

TPC 18. AVO vs. Temperature at±5 V

REV. D–6–