ANALOG DEVICES AD8539 Service Manual

Low Power, Precision, Auto-Zero Op Amps

AD8538/AD8539

FEATURES

Low offset voltage: 13 μV maximum Input offset drift: 0.03 μV/°C Single-supply operation: 2.7 V to 5.5 V High gain, CMRR, and PSRR Low input bias current: 25 pA Low supply current: 180 μA

APPLICATIONS

Mobile communications Portable instrumentation Battery-powered devices Sensor interfaces Temperature measurement

PIN CONFIGURATIONS

OUT

1

AD8538

V–

2

TOP VIEW

(Not to Scale)

+IN

3

Figure 1. 5-Lead TSOT-23 (UJ-5)

NC

1

AD8538

−IN

2

3

+IN

TOP VIEW

(Not to Scale)

4

V−

NC = NO CONNECT

Figure 2. 8-Lead SOIC_N (R-8)

V+

5

–IN

4

06741-002

NC

8

V+

7

6

OUT

5

NC

06741-001

Electronic scales

GENERAL DESCRIPTION

The AD8538/AD8539 are very high precision amplifiers featuring extremely low offset voltage, low input bias current, and low power consumption. The supply current is less than 215 μA maximujm per amplifier at 5.0 V. Operation is fully specified from 2.7 V to

1

OUT A

–IN A

+IN A

V–

AD8539

2

3

TOP VIEW

(Not to Scale)

4

Figure 3. 8-Lead SOIC_N (R-8)

8

7

6

5

V+

OUT B

–IN B

+IN B

06741-033

5.0 V single supply (±1.35 V to ±2.5 V dual supply).

The AD8538/AD8539 operate at very low power making these amplifiers ideal for battery-powered devices and portable equipment.

The AD8538/AD8539 are specified over the extended industrial temperature range (−40°C to +125°C). The AD8538 amplifier is

1

OUT A

–IN A

+IN A

V–

AD8539

2

TOP VIEW

3

(Not to Scale)

4

Figure 4. 8-Lead MSOP (RM-8)

8

7

6

5

V+

OUT B

–IN B

+IN B

06741-034

available in 5-lead TSOT-23, and 8-lead, narrow body SOIC packages, and the AD8539 amplifier is available in 8-lead, narrow body SOIC and 8-lead MSOP.

Rev. A

Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Anal og Devices for its use, nor for any infringements of patents or ot her 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.

AD8538/AD8539

TABLE OF CONTENTS

Features .............................................................................................. 1

Applications....................................................................................... 1

General Description......................................................................... 1

Pin Configurations ........................................................................... 1

Revision History ............................................................................... 2

Specifications..................................................................................... 3

AD8538 Electrical Specifications ............................................... 3

AD8539 Electrical Specifications ............................................... 5

REVISION HISTORY

5/07—Rev. 0 to Rev. A

Added AD8539 ...................................................................Universal

Changes to Specifications Section.................................................. 3

Added Table 3, Renumbered Tables Sequentially ........................ 5

Added Table 4, Renumbered Tables Sequentially ........................ 6

Changes to Thermal Resistance Section........................................ 7

Added Figure 32 and Figure 33..................................................... 13

Added AD8539 Characteristics Section, Renumbered Figures

Sequentially ..................................................................................... 14

Absolute Maximum Ratings ............................................................7

Thermal Resistance .......................................................................7

ESD Caution...................................................................................7

Typical Perf or m an c e Charac t e r istics ..............................................8

AD8538 Characteristics................................................................8

AD8539 Characteristics............................................................. 14

Outline Dimensions ....................................................................... 20

Ordering Guide .......................................................................... 21

Updated Outline Dimensions....................................................... 20

Changes to Ordering Guide.......................................................... 21

10/05—Revision 0: Initial Version

Rev. A | Page 2 of 24

AD8538/AD8539

SPECIFICATIONS

AD8538 ELECTRICAL SPECIFICATIONS

@ VS = 5.0 V, VCM = 2.5 V, VO = 2.5 V, TA = 25°C, unless otherwise specified.

Table 1.

Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS

Offset Voltage V

OS

−40°C ≤ TA ≤ +125°C 30 µV Input Bias Current I

B

−40°C ≤ TA ≤ +85°C 35 100 pA

−40°C ≤ TA ≤ +125°C 0.7 1.0 nA Input Offset Current I

OS

−40°C ≤ TA ≤ +125°C 150 pA Input Voltage Range 0 5 V Common-Mode Rejection Ratio CMRR VCM = 0 V to 5 V 115 150 dB

−40°C ≤ TA ≤ +125°C, VCM = 0.2 V to 4.8 V 100 135 dB Large Signal Voltage Gain A

VO

−40°C ≤ TA ≤ +125°C 110 135 dB Offset Voltage Drift

ΔV

OS

OUTPUT CHARACTERISTICS

Output Voltage High V

OH

−40°C ≤ TA ≤ +125°C, RL = 100 kΩ to ground 4.98 V R

−40°C ≤ TA ≤ +125°C, RL = 10 kΩ to ground 4.94 V Output Voltage Low V

OL

−40°C ≤ TA ≤ +125°C, RL = 100 kΩ to V+ 2.8 7 mV R

−40°C ≤ TA ≤ +125°C, RL = 10 kΩ to V+ 20 30 mV Short-Circuit Limit I

SC

POWER SUPPLY

Power Supply Rejection Ratio PSRR VS = 2.7 V to 5.0 V 105 125 dB

−40°C ≤ TA ≤ +125°C 100 125 dB Supply Current/Amplifier I

SY

−40°C ≤ TA ≤ +125°C 190 215 µA DYNAMIC PERFORMANCE

Slew Rate SR RL =10 kΩ 0.4 V/µs Settling Time 0.01% t

S

Overload Recovery Time 0.05 ms Gain Bandwidth Product GBP 430 kHz Phase Margin Ø

M

NOISE PERFORMANCE

Voltage Noise e Voltage Noise Density e

n p-p

n

5 13 µV

15 25 pA

20 50 pA

RL = 10 kΩ, VO = 0.1 V to 4.9 V 115 141 dB

/ΔT

−40°C ≤ T

≤ +125°C 0.03 0.1 µV/°C

A

RL = 100 kΩ to ground 4.99 4.998 V

= 10 kΩ to ground 4.95 4.970 V

L

RL = 100 kΩ to V+ 1.9 5 mV

= 10 kΩ to V+ 17 20 mV

L

±25 mA

IO = 0 150 180 µA

G = ±1, 2 V step, CL = 20 pF, RL = 1 kΩ 10 s

RL = 10 kΩ, RL = 100 kΩ, CL = 20 pF 65 Degrees

f = 0.1 Hz to 10 Hz 2.0 µV p-p f = 1 kHz 50

nV/√Hz

Rev. A | Page 3 of 24

AD8538/AD8539

@ VS = 2.7 V, VCM = 1.35 V, VO = 1.35 V, TA = 25°C, unless otherwise specified.

Table 2.

Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS

Offset Voltage V

OS

−40°C ≤ TA ≤ +125°C 30 µV Input Bias Current I

B

−40°C ≤ TA ≤ +85°C 35 100 pA

−40°C ≤ TA ≤ +125°C 0.7 1.0 nA Input Offset Current I

OS

−40°C ≤ TA ≤ +125°C 150 pA Input Voltage Range 0 2.7 V Common-Mode Rejection Ratio CMRR VCM = 0 V to 2.5 V 110 140 dB

−40°C ≤ TA ≤ +125°C 100 135 dB Large Signal Voltage Gain A

VO

−40°C ≤ TA ≤ +125°C 105 135 dB Offset Voltage Drift

ΔV

OS

OUTPUT CHARACTERISTICS

Output Voltage High V

OH

−40°C ≤ TA ≤ +125°C, RL = 100 kΩ to ground 2.68 V R

−40°C ≤ TA ≤ +125°C, RL = 10 kΩ to ground 2.66 V Output Voltage Low V

OL

−40°C ≤ TA ≤ +125°C, RL = 100 kΩ to V+ 2.4 5 mV R

−40°C ≤ TA ≤ +125°C, RL = 10 kΩ to V+ 20 25 mV Short-Circuit Limit I

SC

POWER SUPPLY

Power Supply Rejection Ratio PSRR VS = 2.7 V to 5.5 V 105 125 dB

−40°C ≤ TA ≤ +125°C 100 125 dB Supply Current/Amplifier I

SY

−40°C ≤ TA ≤ +125°C 190 215 µA DYNAMIC PERFORMANCE

Slew Rate SR RL = 10 kΩ 0.35 V/µs Settling Time 0.01% t

S

Overload Recovery Time 0.05 ms Gain Bandwidth Product GBP 430 kHz Phase Margin Ø

M

NOISE PERFORMANCE

Voltage Noise e Voltage Noise Density e

n p-p

n

5 13 µV

15 25 pA

20 50 pA

RL = 10 kΩ, VO = 0.1 V to 1.7 V 110 140 dB

/ΔT

−40°C ≤ T

≤ +125°C 0.03 0.1 µV/°C

A

RL = 100 kΩ to ground 2.68 2.698 V

= 10 kΩ to ground 2.67 2.68 V

L

RL = 100 kΩ to V+ 1.7 5 mV

= 10 kΩ to V+ 14 20 mV

L

±8 mA

IO = 0 150 180 µA

G = ±1, 1 V step, CL = 20 pF, RL = 1 kΩ 5 s

RL = 10 kΩ, RL = 100 kΩ, CL = 20 pF 65 Degrees

f = 0.1 Hz to 10 Hz 2.0 µV p-p f = 1 kHz 50

nV/√Hz

Rev. A | Page 4 of 24

AD8538/AD8539

AD8539 ELECTRICAL SPECIFICATIONS

@ VS = 5.0 V, VCM = 2.5 V, VO = 2.5 V, TA = 25°C, unless otherwise specified.

Table 3.

Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS

Offset Voltage V

OS

−40°C ≤ TA ≤ +125°C 30 µV Input Bias Current I

B

−40°C ≤ TA ≤ +85°C 35 125 pA

−40°C ≤ TA ≤ +125°C 0.7 1.0 nA Input Offset Current I

OS

−40°C ≤ TA ≤ +125°C 400 pA Input Voltage Range 0 5 V

−40°C ≤ TA ≤ +125°C 0.2 4.8 V

Common-Mode Rejection Ratio CMRR VCM = 0 V to 5 V 115 135 dB

−40°C ≤ TA ≤ +125°C, VCM = 0.2 V to 4.8 V 100 130 dB Large Signal Voltage Gain A

VO

−40°C ≤ TA ≤ +125°C 110 125 dB Offset Voltage Drift

ΔV

OS

OUTPUT CHARACTERISTICS

Output Voltage High V

OH

−40°C ≤ TA ≤ +125°C, RL = 100 kΩ to ground 4.98 V R

−40°C ≤ TA ≤ +125°C, RL = 10 kΩ to ground 4.94 V Output Voltage Low V

OL

−40°C ≤ TA ≤ +125°C, RL = 100 kΩ to V+ 6 8 mV R

−40°C ≤ TA ≤ +125°C, RL = 10 kΩ to V+ 24 30 mV Short-Circuit Limit I

SC

POWER SUPPLY

Power Supply Rejection Ratio PSRR VS = 2.7 V to 5.0 V 105 125 dB

−40°C ≤ TA ≤ +125°C 100 125 dB Supply Current/Amplifier I

SY

−40°C ≤ TA ≤ +125°C 225 µA DYNAMIC PERFORMANCE

Slew Rate SR RL =10 kΩ 0.4 V/µs Settling Time 0.01% t

S

Overload Recovery Time 0.05 ms Gain Bandwidth Product GBP 430 kHz Phase Margin Ø

M

NOISE PERFORMANCE

Voltage Noise e Voltage Noise Density e

n p-p

n

5 15 µV

15 60 pA

20 70 pA

RL = 10 kΩ, VO = 0.1 V to 4.9 V 110 130 dB

/ΔT

−40°C ≤ T

≤ +125°C 0.03 0.1 µV/°C

A

RL = 100 kΩ to ground 4.99 4.994 V

= 10 kΩ to ground 4.95 4.97 V

L

RL = 100 kΩ to V+ 5 7 mV

= 10 kΩ to V+ 20 25 mV

L

±25 mA

IO = 0 170 210 µA

G = ±1, 2 V step, CL = 20 pF, RL = 1 kΩ 10 s

RL = 10 kΩ, RL = 100 kΩ, CL = 20 pF 65 Degrees

f = 0.1 Hz to 10 Hz 1.2 µV p-p f = 1 kHz 52

nV/√Hz

Rev. A | Page 5 of 24

AD8538/AD8539

@ VS = 2.7 V, VCM = 1.35 V, VO = 1.35 V, TA = 25°C, unless otherwise specified.

Table 4.

Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS

Offset Voltage V

OS

−40°C ≤ TA ≤ +125°C 30 µV Input Bias Current I

B

−40°C ≤ TA ≤ +85°C 35 125 pA

−40°C ≤ TA ≤ +125°C 0.7 1.0 nA Input Offset Current I

OS

−40°C ≤ TA ≤ +125°C 300 pA Input Voltage Range 0 2.7 V

−40°C ≤ TA ≤ +125°C 0.2 2.5 Common-Mode Rejection Ratio CMRR VCM = 0 V to 2.7 V 110 130 dB

−40°C ≤ TA ≤ +125°C, VCM = 0.2 V to 2.5 V 100 125 dB Large Signal Voltage Gain A

VO

−40°C ≤ TA ≤ +125°C 105 125 dB Offset Voltage Drift

ΔV

OS

OUTPUT CHARACTERISTICS

Output Voltage High V

OH

−40°C ≤ TA ≤ +125°C, RL = 100 kΩ to ground 2.68 V R

−40°C ≤ TA ≤ +125°C, RL = 10 kΩ to ground 2.66 V Output Voltage Low V

OL

−40°C ≤ TA ≤ +125°C, RL = 100 kΩ to V+ 6 8 mV R

−40°C ≤ TA ≤ +125°C, RL = 10 kΩ to V+ 20 25 mV Short-Circuit Limit I

SC

POWER SUPPLY

Power Supply Rejection Ratio PSRR VS = 2.7 V to 5.5 V 105 125 dB

−40°C ≤ TA ≤ +125°C 100 125 dB Supply Current/Amplifier I

SY

−40°C ≤ TA ≤ +125°C 225 µA DYNAMIC PERFORMANCE

Slew Rate SR RL = 10 kΩ 0.35 V/µs Settling Time 0.01% t

S

Overload Recovery Time 0.05 ms Gain Bandwidth Product GBP 430 kHz Phase Margin Ø

M

NOISE PERFORMANCE

Voltage Noise e Voltage Noise Density e

n p-p

n

5 16 µV

15 25 pA

20 50 pA

RL = 10 kΩ, VO = 0.1 V to 2.6 V 110 130 dB

/ΔT

−40°C ≤ T

≤ +125°C 0.03 0.1 µV/°C

A

RL = 100 kΩ to ground 2.68 2.693 V

= 10 kΩ to ground 2.67 2.68 V

L

RL = 100 kΩ to V+ 5 7 mV

= 10 kΩ to V+ 14 20 mV

L

±8 mA

IO = 0 210 µA

G = ±1, 1 V step, CL = 20 pF, RL = ∞ 8 s

RL = 10 kΩ, RL = 100 kΩ, CL = 20 pF 65 Degrees

f = 0.1 Hz to 10 Hz 2.0 µV p-p f = 1 kHz 55

nV/√Hz

Rev. A | Page 6 of 24

AD8538/AD8539

ABSOLUTE MAXIMUM RATINGS

T = 25°C, unless otherwise noted.

A

Table 5.

Parameter Rating

Supply Voltage +6 V Input Voltage V − 0.3 V to V + 0.3 V Differential Input Voltage ±6 V Output Short-Circuit Duration to GND Observe derating curve Storage Temperature Range –65°C to +150°C Lead Temperature (Soldering, 60 sec) 300°C Operating Temperature Range –40°C to +125°C Junction Temperature Range −65°C to +150°C

SS DD

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.

Absolute maximum ratings apply at 25°C, unless otherwise noted.

THERMAL RESISTANCE

θ

is specified for the worst-case conditions, that is, a device

JA

soldered in a circuit board for surface-mount packages.

Table 6. Thermal Characteristics

Package Type θ θ Unit

5-Lead TSOT-23 (UJ-5) 207 61 °C/W 8-Lead SOIC_N (R-8) 125 43 °C/W 8-Lead MSOP (RM-8) 145 45 °C/W

JA JC

ESD CAUTION

Rev. A | Page 7 of 24

AD8538/AD8539

TYPICAL PERFORMANCE CHARACTERISTICS

AD8538 CHARACTERISTICS

AD8538 only, V = 5 V or ±2.5 V, unless otherwise noted.

450

400

350

300

250

200

150

NUMBER OF AMPLIFIERS

100

50

SY

VSY = 5V 0V < V

< 5V

CM

T

= 25°C

A

0

–10.0

–8.4 –6.8 –5.2 –3.6 –2.0 –0.4 1.2 2.8 4.4 6.0 7.6 9.2

INPUT OFFSET VOLTAGE (µV)

06741-003

Figure 5. AD8538 Input Offset Voltage Distribution Figure 8. AD8538 Input Bias Current vs. Temperature

700

VSY = 5V AND 2.7V

600

500

400

300

200

INPUT BIAS CURRENT (pA)

100

0

25 45 65 85 105 125

TEMPERATURE (°C)

06741-006

14

V

= 5V

SY

–40°C < T

12

10

8

6

4

NUMBER OF AMPLIFIERS

2

0

0 0.096

< +125°C

A

0.012 0.024 0.0 36 0.048 0.060 0.072 0.084

TCVOS (µV/°C)

06741-004

Figure 6. AD8538 Input Offset Voltage Drift Distribution

10

VSY = 5V T

= 25°C

8

A

6

4

2

0

–2

–4

INPUT OFFSET VOLTAGE (µV)

–6

–8

–10

05

1234

INPUT COMMON-MODE VOLTAGE (V)

06741-005

Figure 7. AD8538 Input Offset Voltage vs. Input Common-Mode Voltage

160

= 25°C

T

A

140

120

100

80

60

SUPPLY CURRENT (µA)

40

20

0

05

Figure 9. AD8538 Supply Current vs. Supply Voltage

200

150

100

SUPPLY CURRENT (µA)

50

0

–40 10 60 110

Figure 10. AD8538 Supply Current vs. Temperature

1234

SUPPLY VOLTAGE (V)

VSY = 5V

= 2.7V

V

SY

TEMPERATURE (°C)

06741-007

06741-008

Rev. A | Page 8 of 24