ANALOG DEVICES AD8271 Service Manual

Programmable Gain

FEATURES

With no external resistors

Difference amplifier, gains of ½, 1, or 2 Single-ended amplifier: over 40 different gains Set reference voltage at midsupply

Excellent ac specifications

15 MHz bandwidth 30 V/μs slew rate

High accuracy dc performance

0.08% maximum gain error 10 ppm/°C maximum gain drift

80 dB minimum CMRR (gain of 2) 10-lead MSOP package Supply current: 2.6 mA Supply range: ±2.5 V to ±18 V

APPLICATIONS

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

Precision Difference Amplifier

AD8271

FUNCTIONAL BLOCK DIAGRAM

Figure 1.

10kΩ

10

N3

9

N2

N1

8

OUT

7

6

+V

S

07363-001

1

P1

2

P2

P3

3

4

P4

5

–V

S

10kΩ

20kΩ

AD8271

GENERAL DESCRIPTION

The AD8271 is a low distortion, precision difference amplifier with internal gain setting resistors. With no external components, it can be configured as a high performance difference amplifier with gains of ½, 1, or 2. It can also be configured in over 40 singleended configurations, with gains ranging from −2 to +3.

The AD8271 comes in a 10-lead MSOP package. The AD8271 operates on both single and dual supplies and requires only a

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 a dual channel version of the AD8271, see the AD8270 data sheet.

Table 1. Difference Amplifiers by Category

High Speed

High Voltage

Single-Supply Unidirectional

Single-Supply Bidirectional

AD8270 AD628 AD8202 AD8205 AD8273 AD629 AD8203 AD8206 AD8274 AD8216 AMP03

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.

AD8271

REVISION HISTORY

1/09—Revision 0: Initial Version

Rev. 0 | Page 2 of 20

AD8271

SPECIFICATIONS

DIFFERENCE AMPLIFIER CONFIGURATIONS

VS = ±5 to ±15 V, V

Table 2.

B Grade A Grade Parameter Conditions Min Typ Max Min Typ Max Unit

DYNAMIC PERFORMANCE

Bandwidth 15 15 MHz Slew Rate 30 30 V/μs Settling Time to 0.01% VS = ±15, 10 V step on output 700 800 700 800 ns V Settling Time to 0.001% VS = ±15, 10 V step on output 750 900 750 900 ns V

NOISE/DISTORTION

Harmonic Distortion + Noise

Voltage Noise1 f = 0.1 Hz to 10 Hz 1.5 1.5 μV p-p f = 1 kHz 38 38 nV/√Hz GAIN

Gain Error V

Gain Drift TA = −40°C to +85°C 1 2 1 10 ppm/°C

Gain Nonlinearity

INPUT CHARACTERISTICS

2

Offset

300 600 300 1000 μV

Average Temperature Drift TA = −40°C to +85°C 2 2 μV/°C Common-Mode Rejection Ratio DC to 1 kHz 80 92 74 92 dB Power Supply Rejection Ratio 2 10 2 10 μV/V Input Voltage Range Common-Mode Resistance Bias Current Inputs grounded 500 500 nA

OUTPUT CHARACTERISTICS

Output Swing VS = ±15 −13.8 +13.8 −13.8 +13.8 V V V V Short-Circuit Current Limit Sourcing 100 100 mA

Sinking 60 60 mA POWER SUPPLY

Supply Current 2.3 2.6 2.3 2.6 mA

T

1

Includes amplifier voltage and current noise, as well as noise of internal resistors.

2

Includes input bias and offset errors.

3

At voltages beyond the rails, internal ESD diodes begin to turn on. In some configurations, the input voltage range may be limited by the internal op amp (see the

4

Internal resistors, trimmed to be ratio matched, have ±20% absolute accuracy. Common-mode resistance was calculated with both inputs in parallel. The common-

mode impedance at only one input is 2× the resistance listed.

= 0 V, G = 1, R

REF

3

−V

4

10 10 kΩ

section for details). Input Voltage Range

= 2 kΩ, TA = 25°C, specifications referred to input (RTI), unless otherwise noted.

LOAD

= ±5, 5 V step on output 550 650 550 650 ns

S

= ±5, 5 V step on output 600 750 600 750 ns

S

= ±15, f = 1 kHz,

V

S

= 10 V p-p, R

V

OUT

= ±5, f = 1 kHz,

V

S

= 10 V p-p, R

V

OUT

= 10 V p-p 0.02 0.05 %

OUT

= 10 V p-p,

V

OUT

= 10 kΩ, 2 kΩ, 600 Ω

R

LOAD

= ±15, TA = −40°C to +85°C −13.7 +13.7 −13.7 +13.7 V

S

= ±5 −4 +4 −4 +4 V

S

= ±5, TA = −40°C to +85°C −3.9 +3.9 −3.9 +3.9 V

S

= −40°C to +85°C 3.2 3.2 mA

A

LOAD

= 600 Ω

110 110 dB

141 141 dB

1 1 ppm

− 0.4 +VS + 0.4 −VS − 0.4 +VS + 0.4 V

S

Rev. 0 | Page 3 of 20

AD8271

VS = ±5 to ±15 V, V

Table 3.

B Grade A Grade Parameter Conditions Min Typ Max Min Typ Max Unit

DYNAMIC PERFORMANCE

Bandwidth 20 20 MHz Slew Rate 30 30 V/μs Settling Time to 0.01% VS = ±15, 10 V step on output 700 800 700 800 ns V Settling Time to 0.001% VS = ±15, 10 V step on output 750 900 750 900 ns V

NOISE/DISTORTION

Harmonic Distortion + Noise

Voltage Noise1 f = 0.1 Hz to 10 Hz 2 2 μV p-p f = 1 kHz 52 52 nV/√Hz GAIN

Gain Error V

Gain Drift TA = −40°C to +85°C 0.5 2 1 10 ppm/°C

Gain Nonlinearity

INPUT CHARACTERISTICS

2

Offset

450 1000 450 1500 μV

Average Temperature Drift TA = −40°C to +85°C 3 3 μV/°C Common-Mode Rejection Ratio DC to 1 kHz 74 86 70 86 dB Power Supply Rejection Ratio 2 10 2 10 μV/V Input Voltage Range Common-Mode Resistance Bias Current Inputs grounded 500 500 nA

OUTPUT CHARACTERISTICS

Output Swing VS = ±15 −13.8 +13.8 −13.8 +13.8 V V V V Short-Circuit Current Limit Sourcing 100 100 mA

Sinking 60 60 mA POWER SUPPLY

Supply Current 2.3 2.6 2.3 2.6 mA

T

1

Includes amplifier voltage and current noise, as well as noise of internal resistors.

2

Includes input bias and offset errors.

3

At voltages beyond the rails, internal ESD diodes begin to turn on. In some configurations, the input voltage range may be limited by the internal op amp (see the

4

Internal resistors, trimmed to be ratio matched, have ±20% absolute accuracy. Common-mode resistance was calculated with both inputs in parallel. The common-

mode impedance at only one input is 2× the resistance listed.

= 0 V, G = ½, R

REF

3

−V

4

7.5 7.5 kΩ

section for details). Input Voltage Range

= 2 kΩ, TA = 25°C, specifications referred to input (RTI), unless otherwise noted.

LOAD

= ±5, 5 V step on output 550 650 550 650 ns

S

= ±5, 5 V step on output 600 750 600 750 ns

S

= ±15, f = 1 kHz,

V

S

= 10 V p-p, R

V

OUT

= ±5, f = 1 kHz,

V

S

= 10 V p-p, R

V

OUT

= 10 V p-p 0.04 0.08 %

OUT

= 10 V p-p,

V

OUT

= 10 kΩ, 2 kΩ, 600 Ω

R

LOAD

= ±15, TA = −40°C to +85°C −13.7 +13.7 −13.7 +13.7 V

S

= ±5 −4 +4 −4 +4 V

S

= ±5, TA = −40°C to +85°C −3.9 +3.9 −3.9 +3.9 V

S

= −40°C to +85°C 3.2 3.2 mA

A

LOAD

= 600 Ω

74 74 dB

101 101 dB

200 200 ppm

− 0.4 +VS + 0.4 −VS − 0.4 +VS + 0.4 V

S

Rev. 0 | Page 4 of 20

AD8271

VS = ±5 to ±15 V, V

Table 4.

B Grade A Grade Parameter Conditions Min Typ Max Min Typ Max Unit

DYNAMIC PERFORMANCE

Bandwidth 10 10 MHz Slew Rate 30 30 V/μs Settling Time to 0.01% VS = ±15, 10 V step on output 700 800 700 800 ns V Settling Time to 0.001% VS = ±15, 10 V step on output 750 900 750 900 ns V

NOISE/DISTORTION

Harmonic Distortion + Noise

Voltage Noise1 f = 0.1 Hz to 10 Hz 1 1 μV p-p f = 1 kHz 26 26 nV/√Hz GAIN

Gain Error V

Gain Drift TA = −40°C to +85°C 0.5 2 1 10 ppm/°C

Gain Nonlinearity

INPUT CHARACTERISTICS

2

Offset

225 500 225 750 μV

Average Temperature Drift TA = −40°C to +85°C 1.5 1.5 μV/°C Common-Mode Rejection Ratio DC to 1 kHz 84 98 78 98 dB Power Supply Rejection Ratio 2 10 2 10 μV/V Input Voltage Range Common-Mode Resistance Bias Current Inputs grounded 500 500 nA

OUTPUT CHARACTERISTICS

Output Swing VS = ±15 −13.8 +13.8 −13.8 +13.8 V V V V Short-Circuit Current Limit Sourcing 100 100 mA

Sinking 60 60 mA POWER SUPPLY

Supply Current 2.3 2.6 2.3 2.6 mA

T

1

Includes amplifier voltage and current noise, as well as noise of internal resistors.

2

Includes input bias and offset errors.

3

At voltages beyond the rails, internal ESD diodes begin to turn on. In some configurations, the input voltage range may be limited by the internal op amp (see the

4

Internal resistors, trimmed to be ratio matched, have ±20% absolute accuracy. Common-mode resistance was calculated with both inputs in parallel. The common-

mode impedance at only one input is 2× the resistance listed.

= 0 V, G = 2, R

REF

3

−V

4

7.5 7.5 kΩ

section for details). Input Voltage Range

= 2 kΩ, TA = 25°C, specifications referred to input (RTI), unless otherwise noted.

LOAD

= ±5, 5 V step on output 550 650 550 650 ns

S

= ±5, 5 V step on output 600 750 600 750 ns

S

= ±15, f = 1 kHz,

V

S

= 10 V p-p, R

V

OUT

= ±5, f = 1 kHz,

V

S

= 10 V p-p, R

V

OUT

= 10 V p-p 0.04 0.08 %

OUT

= 10 V p-p,

V

OUT

= 10 kΩ, 2 kΩ, 600 Ω

R

LOAD

= ±15, TA = −40°C to +85°C −13.7 +13.7 −13.7 +13.7 V

S

= ±5 −4 +4 −4 +4 V

S

= ±5, TA = −40°C to +85°C −3.9 +3.9 −3.9 +3.9 V

S

= −40°C to +85°C 3.2 3.2 mA

A

LOAD

= 600 Ω

86 86 dB

112 112 dB

50 50 ppm

− 0.4 +VS + 0.4 −VS − 0.4 +VS + 0.4 V

S

Rev. 0 | Page 5 of 20

AD8271

ABSOLUTE MAXIMUM RATINGS

Table 5.

Parameter Rating

Supply Voltage ±18 V Output Short-Circuit Current

Input Voltage Range

See derating curve in Figure 2

+ 0.4 V to

+V

S

−V

− 0.4 V

S

Storage Temperature Range −65°C to +130°C Specified Temperature Range −40°C to +85°C Package Glass Transition Temperature (TG) 150°C ESD

Human Body Model 1 kV Charge Device Model 1 kV Machine Model 0.1 kV

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

Table 6. Thermal Resistance

Package Type θJA θ

10-Lead MSOP 141.9 43.7 °C/W

The θJA values in Table 6 assume a 4-layer JEDEC standard board with zero airflow.

Unit

JC

MAXIMUM POWER DISSIPATION

The maximum safe power dissipation for the AD8271 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 of time can cause changes in silicon devices, potentially resulting in a loss of functionality.

The AD8271 has built-in short-circuit protection that limits the output current to approximately 100 mA (see Figure 22 for more information). Although 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.

1.6

1.4

1.2

1.0

0.8

0.6

0.4

MAXIMUM POWER DISSIPATION (W)

0.2

0

–50 –25 0 25 50 75 100 125

Figure 2. Maximum Power Dissipation vs. Ambient Temperature

AMBIENT TEMPERATURE (C)

TJ MAX = 150°C

) on the die. At

J

07363-102

ESD CAUTION

Rev. 0 | Page 6 of 20

ANALOG DEVICES AD8271 Service Manual

FEATURES

APPLICATIONS

FUNCTIONAL BLOCK DIAGRAM

GENERAL DESCRIPTION

TABLE OF CONTENTS

REVISION HISTORY

SPECIFICATIONS

DIFFERENCE AMPLIFIER CONFIGURATIONS

ABSOLUTE MAXIMUM RATINGS

THERMAL RESISTANCE

MAXIMUM POWER DISSIPATION

ESD CAUTION