AA and AB-Series Analog Sensors

AA and AB-Series Analog Sensors

AA and AB-Series Analog Sensors

NVE’s AA and AB-Series analog GMR sensors offer unique and unparalleled magnetic sensing capabilities. These sensors are characterized by high sensitivity to applied magnetic fields, excellent temperature stability, low power consumption, and small size. These characteristics make them suitable for use in a wide variety of applications from rugged industrial and automotive position, speed, and current sensors, to low-voltage, battery-powered sensors for use in hand-held instrumentation and implantable medical devices. The unmatched versatility of these basic magnetic sensors makes them an excellent choice for a wide range of analog sensing applications.

The AA-Series sensors use NVE’s patented GMR materials and on-chip flux concentrators to provide a directionally sensitive output signal. These sensors are sensitive in one direction in the plane of the

IC, with a cosine-scaled falloff in sensitivity as the sensor is rotated away from the sensitive direction.

Also, these devices provide the same output for magnetic fields in the positive or negative direction along the axis of sensitivity (omnipolar output). All sensors are designed in a Wheatstone bridge configuration to provide temperature compensation. Two packages are offered, an SOIC8 and an

MSOP8. These sensors are also available in die form on a special-order basis.

There are three families of NVE’s basic AA-Series sensors: the standard AA-Series, the AAH-Series, and the AAL-Series. Each of these sensor families uses a different GMR material, with its own characteristics. The comparison table below summarizes the different characteristics of the GMR materials:

Parameter AA Series

Sensitivity to Applied Fields High

Field Range of Operation High

AAH Series

Low

AAL Series

Medium

Temperature Range High Very High Very High

The AB-Series sensors are differential sensor devices, or gradiometers, which take advantage of the high output characteristics of NVE’s GMR materials. Two families of AB sensors are offered, the standard AB-Series and the ABH-Series. They have operational characteristics similar to the AA and

AAH sensors described in the table above but with the bipolar linear output characteristics of a differential sensor.

Within these different sensor families, customers can find an excellent match to their analog sensor requirements.

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AA and AB-Series Analog Sensors

Quick Reference: AA and AB-Series

For comparison and product selection purposes, the following table lists all available AA and AB-

Series analog sensors, with some of their key characteristics:

Magnetometers:

Part

Number

Linear

Range

(|Oe

1

|)

Sensitivity

(mV/V-Oe

1

)

Maximum

Nonlinearity

(% Uni.

2

)

AA002-02 1.5 10.5 3.0 4.2 2

AA003-02 2.0 2

0.9 2

0.9 2

0.45 2

0.9 2

0.9 2

AAH002-02 0.6 3.0 11.0 6

AAH004-00 1.5 7.5 3.2 4.8

AAL002-02 1.5 10.5 3.0 4.2

4

2

Gradiometers:

Maximum

Hyster- esis

(% Uni.

2

)

4

4

4

4

4

4

4

15

15

2

Maximum

Operating

Temp

(°C)

125

125

125

125

Typical

Resistance

(Ohms) Package

5K SOIC8

5K SOIC8

5K MSOP8

5K SOIC8

125 5K SOIC8

125 30K MSOP8

125 30K SOIC8

150 2K SOIC8

150

150

2K MSOP8

5.5K SOIC8

Part

Number

Linear

Range

(|Oe

1

|)

Resistor

Spacing

(mm)

Maximum

Nonlinearity

(% Uni.

2

)

2

2

4

Maximum

Hyster- esis

(% Uni.

2

)

4

4

15

Maximum

Operating

Temp

Typical

Resistance

(Ohms) Package (°C)

125 2.5K SOIC8

125 2.5K MSOP8

150 1.2K MSOP8 ABH001-00 5 40 0.5

Notes

:

1. Oersted (Oe) = 1 Gauss in air.

2. Unipolar operation means exposure to magnetic fields of one polarity, for example 0 to +30 Gauss, or -2 to -50 Gauss.

Bipolar operation (for example, -5 to +10 Gauss) will increase nonlinearity and hysteresis

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AA Sensors

AA Sensors

Features:

• Excellent Sensitivity to Applied Magnetic Fields

• Wheatstone Bridge Analog Output

• Operating Temperature to 125°C Continuous

• Wide Linear Range of Operation

• Near-Zero Voltage Operation

• DC to >1MHz Frequency Response

• Small, Low-Profile Surface Mount Packages

Applications:

• General Motion, Speed, and Position Sensing

• Low Power, Low Voltage Applications

• Low Field Sensing for Magnetic Media Detection

• Current Sensing

Description:

The basic AA-Series GMR sensors are general-purpose magnetometers for use in a wide variety of applications. They exhibit excellent linearity, a large output signal with applied magnetic fields, stable and linear temperature characteristics, and a purely ratiometric output.

V+ (supply)

Pin-out

OUT+

Functional Block Diagram pin 8,

V+(supply)

NVE

NVE

AAxxx

AAXXX-02

-02 shield

GMR pin 5, OUT+

Orientation shield pin 1, OUT-

OUT V- (ground)

Axis of Sensitivity pin 4, V-

(ground)

Magnetic Characteristics:

Part

Number

Saturation

Field (Oe

1

)

AA002-02 15

Linear

Range

(|Oe

1

|)

Sensitivity

(mV/V-Oe

1

)

Resistance

(Ohms) Package

2

Min Max Min Max

1.5 10.5 3.0 4.2 5K SOIC8 436x3370

3.2 ±20%

Die Size

3

(

µ

m)

1.3 ±20%

1.3 ±20%

0.65 ±20%

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General Characteristics:

Input Voltage Range

Operating Frequency

Operating Temperature Range

Bridge Electrical Offset

Signal Output at Max. Field

<1

4

DC

-50

-4

24

4

>1

125

60

+4

Volts

MHz

°

C mV/V mV/V

AA Sensors

Off Axis Characteristic

ESD Tolerance

Notes:

% /

°

C

-0.1

Cos

β

7

400 V pin-to-pin HBM

1. 1 Oersted (Oe) = 1 Gauss in air.

2. See the Appendix for package dimensions and tolerances.

3. Sensors can be provided in die form by special request.

A-Series

sensors are pure ratiometric devices meaning that they will operate properly at extremely low supply voltages

.

The output signal will be proportional to the supply voltage

.

Maximum voltage range is limited by the power dissipation in the package and the maximum operating temperature of the sensor.

5. Unipolar operation means exposure to magnetic fields of one polarity, e.g., 0 to 30 Gauss, or 2 to -50 Gauss, but not -20 to

+30 Gauss (bipolar operation)

.

Bipolar operation will increase nonlinearity and hysteresis.

6. TCR is resistance change with temperature with no applied field

.

TCOI is the output change with temperature using a constant current source to power the sensor

.

TCOV is the output change with temperature using a constant voltage source to power the sensor

.

See the graphs below.

AA002 Tem perature Performance, 5V Supply

AA002 Te mperature Performa nce,

1m A Curre nt Supply

0.35

0.3

0.25

0.35

0.3

0.25

0.2

0.15

0.1

0.05

-40C

25C

85C

125C

0

-20

-0.05

-15 -10 -5 0 5

Applie d M agnetic Field (Oe)

10 15 20

0.2

0.15

0.1

0.05

- 15 -

0

-20

-0.05

-15 -10 -5 0 5

Applied Magnetic Field (Oe)

10

-40C

25C

85C

125C

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AAH Sensors

AAH Sensors

Features:

• Extremely High Sensitivity to Applied Magnetic Fields

• Wheatstone Bridge Analog Output

• Temperature Tolerance to 150°C Continuous

• Near-Zero Voltage Operation

• DC to >1MHz Frequency Response

• Small, Low-Profile Surface Mount Packages

Applications:

• Low Voltage, High Temperature Applications

• Low Field Sensing for Magnetic Media Detection

• Earth’s Magnetic Field Detection

• Current Sensing

Description:

The AAH-Series GMR sensors are manufactured with a high sensitivity GMR material, making them ideally suited for any low magnetic field application. They are also extremely temperature tolerant, to

+150°C operating temperatures.

V+ (supply)

Pin-out

OUT+

NVE

NVE

AAxxx

AAXXX-02

Functional Block Diagram pin 8,

V+(supply) shield

GMR pin 5, OUT+

Orientation shield pin 1, OUT-

OUT V- (ground)

Axis of Sensitivity

Magnetic Characteristics:

pin 4, V-

(ground)

Part

Number

Saturation

Field (Oe

1

)

Linear

Range

(|Oe

1

|)

Sensitivity

(mV/V-Oe

1

)

Resistance

(Ohms) Package

2

Die Size

3

(

µ

m)

AAH004-00 15 1.5 7.5 3.2 4.8 2K MSOP 411x1458

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General Characteristics:

AAH Sensors

Input Voltage Range

Operating Frequency

Operating Temperature Range

Bridge Electrical Offset

Signal Output at Max. Field

Nonlinearity

Hysteresis

<1

4

DC

-50

-5

±12

4

>1

150

40

+5

Volts

MHz

°

C mV/V mV/V

Off Axis Characteristic

ESD Tolerance

Notes:

% /

°

C

0.0

Cos

β

7

400 V pin-to-pin HBM

1. 1 Oersted (Oe) = 1 Gauss in air.

2. See the Appendix for package dimensions and tolerances.

3. Sensors can be provided in die form by special request.

4. GMR AAH-Series sensors are pure ratiometric devices meaning that they will operate properly at extremely low supply voltages

.

The output signal will be proportional to the supply voltage

.

Maximum voltage range is limited by the power dissipation in the package and the maximum operating temperature of the sensor.

5. Unipolar operation means exposure to magnetic fields of one polarity, e.g. 0 to 30 Gauss, or -2 to -50 Gauss, but not -20 to

+30 Gauss (bipolar operation)

.

Bipolar operation will increase nonlinearity and hysteresis.

6. TCR is resistance change with temperature with no applied field

.

TCOI is the output change with temperature using a constant current source to power the sensor

.

TCOV is the output change with temperature using a constant voltage source to power the sensor.

0.4

0.35

0.3

0.25

0.2

0.15

0.1

0.05

0

-20

-0.05

AAH002 Temperature Performance,

2.28mA Current Source

-15 -10 -5 0 5 10

Applied Magnetic Field (Oe)

-40C

25C

85C

125C

15 20

AAH002 Temperature Performance, 5V Supply

0.4

0.35

0.3

0.25

0.2

0.15

0.1

0.05

0

-0.05

-20 -15 -10 -5 0 5

Applied Magnetic Field (Oe)

10

-40C

25C

85C

125C

15 20

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AAL Sensors

AAL Sensors

Features:

• Excellent Sensitivity to Applied Magnetic Fields

• Wheatstone Bridge Analog Output

• Temperature Tolerance to 150°C Continuous

• Very Low Magnetic Hysteresis

• Near-Zero Voltage Operation

• DC to >1MHz Frequency Response

• Small, Low-Profile Surface Mount Packages

Applications:

• General Motion, Speed, and Position Sensing

• Low Voltage, High Temperature Applications

• Low Field Sensing for Magnetic Media Detection

• Current Sensing

Description:

The AAL-Series GMR sensors are manufactured with a low hysteresis GMR material, for use in magnetometer applications where minimum hysteresis is important. They are also extremely temperature tolerant, to +150°C operating temperatures.

V+ (supply)

Pin-out

OUT+

NVE

NVE

AAxxx

AAXXX-02

-02

Functional Block Diagram pin 8,

V+(supply) shield

GMR pin 5, OUT+

Orientation shield pin 1, OUT-

OUT V- (ground)

Axis of Sensitivity

Magnetic Characteristics:

pin 4, V-

(ground)

Part

Number

Saturation

Field (Oe

1

)

Linear

Range

(|Oe

1

|)

Sensitivity

(mV/V-Oe

1

)

Resistance

(Ohms) Package

2

Die Size

3

(

µ

m)

AAL002-02 15

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General Characteristics:

Input Voltage Range

Operating Frequency

Operating Temperature Range

Bridge Electrical Offset

Signal Output at Max. Field

<1

4

DC

-50

-4

±25

4

>1

150

45

+4

Volts

MHz

°

C mV/V mV/V

AAL Sensors

0.35

0.3

0.25

0.2

0.15

0.1

0.05

0

-30

-0.05

Off Axis Characteristic

ESD Tolerance

Notes:

% /

°

C

-0.40

Cos

β

7

400 V pin-to-pin HBM

1. 1 Oersted (Oe) = 1 Gauss in air.

2. See the Appendix for package dimensions and tolerances.

3. Sensors can be provided in die form by special request.

4. GMR AAL-Series sensors are pure ratiometric devices meaning that they will operate properly at extremely low supply voltages

.

The output signal will be proportional to the supply voltage

.

Maximum voltage range is limited by the power dissipation in the package and the maximum operating temperature of the sensor.

5. Unipolar operation means exposure to magnetic fields of one polarity, e.g. 0 to 30 Gauss, or -2 to -50 Gauss, but not -20 to

+30 Gauss (bipolar operation)

.

Bipolar operation will increase nonlinearity and hysteresis.

6. TCR is resistance change with temperature with no applied field

.

TCOI is the output change with temperature using a constant current source to power the sensor

.

TCOV is the output change with temperature using a constant voltage source to power the sensor.

AAL002 Temperature Performance,

1mA Current Supply

-40C

25C

85C

125C

-20 -10 0 10

Applied Magnetic Field (Oe)

20 30

0.35

AAL002 Temperature Performance, 5V Supply

0.3

0.25

0.2

0.15

0.1

0.05

0

-30

-0.05

-20 -10 0

-40C

25C

85C

125C

10 20 30

Applie d M ag ne tic F ie ld (O e )

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AAV Sensors

AAV Sensors

Features:

• Operates in Magnetic Saturation, 30 to 200 Gauss

• Half-Bridge or Individual Resistor Configurations

• Sine and Cosine Outputs Available

• Utilizes Spin Valve GMR Material

• Precise Detection of Magnetic Field

• Ultra-Small PLLP Package

• Cannot Be Damaged by Large External Magnetic Fields

Description:

The AAV001-11 and AAV002-11 are arrays of four GMR resistors rotated at 90-degree intervals in the package. The AAV001-11 features independent resistors that can be wired together to form two half-bridges, or used as independent resistors. The AAV002-11 has the bridge connections made internally to the package. For either part, the output can be configured to represent the sine and cosine function of the magnetic field being applied to the sensor. Each resistor is 1.5 k

Ω nominal resistance and output of each half-bridge is ratiometric with the power supply voltage. The part features NVE’s

PLLP6 housing, which is a 3.0 mm x 3.0 mm x 0.9 mm thick surface mount package.

Operation:

The sensor elements contain two magnetic layers: a pinned, or fixed-direction layer, and a movable or free layer. The diagram below illustrates the configuration with arrows representing the two layers:

Angle Between Pinned and Free Layers

Determines Electrical

Resistance of Sensor

Free Layer

Free Layer Aligns with the Applied

Magnetic Field

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AAV Sensors

The end user must apply a saturating magnetic field (30 to 200 Oersteds) in the plane of the sensor in order for the sensor to operate. The movable layer will align with the applied magnetic field. As the applied field changes direction the angle between the movable layer and the pinned layer changes, resulting in a change of resistance in the device. A graph of the device resistance vs. the angle between the pinned layer and the movable layer is shown below:

Resistance Change of Spin Valve

Sensor Element

1520

1510

1500

1490

1480

1470

1460

1450

1440

1430

1420

0 90 180 270 360

Angle Between Pinned and Movable Layers

Four individual sensor resistors are supplied in the package, each with the pinned layer rotated 90º with respect to that of the previous sensor. These resistors can be connected in two half-bridge configurations to provide a sine and cosine output or monitored individually to provide an absolute indication of the angle between the pinned layer and the movable layer.

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AAV Sensors

A drawing showing the ICs position in the package is given below. On each IC there is an arrow indicating the direction of the pinned layer.

Functional Block Diagram, Marking, and Pinout, AAV001-11:

R3

VCC

BBP

R3 (Cosine)

R2

R2 (Sine)

GND

R1

R1 (Sine) R4 (Cosine)

R4

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Cosine Output

Sine Output

Functional Block Diagram, Marking, and Pinout, AAV002-11:

Cosine Output

VCC

BBQ

R3 (Cosine) R2 (Sine)

Cos Sin

R4 (Cosine) R1 (Sine)

GND

AAV Sensors

Sine Output

Specifications:

Parameter

Nominal Resistance of Each Resistor

Maximum Resistance Decrease with Field

Change

Required Strength of Applied Magnetic Field

Measurement Error

Supply Voltage

Offset Voltage

Temperature Range of Operation

Storage Temperature

Temperature Coefficient of Resistance Operating

TCOV

3

TCOI

3

Operating

Notes

:

Test

Condition Min Typ Max Units

1200 1500 1800 Ohms 25°C

Operating at

25°C

Operating

Operating

30 200

2

Oersted

2

Degrees

12 Volts Operating

Operating at

25°C

Operating -40

-40

150

170

°

C

°

C

+0.3

-0.24

%/

°

C

%/

°

C

1. Large Magnetic Fields WILL NOT cause damage to NVE GMR Sensors.

2. 1 Oe (Oersted) = 1 Gauss in air = 0.1 mTesla = 79.8 Amps/meter.

3. TCOV is the percent change in output signal over temperature with a constant voltage source powering the part and TCOI is the percent change in output over temperature with a constant current source.

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AB Sensors

AB Sensors

Features:

• Excellent Sensitivity to Applied Magnetic Fields

• Wheatstone Bridge Analog Output

• Temperature Tolerance to 125°C Continuous

• Wide Linear Range of Operation

• Near-Zero Voltage Operation

• DC to >1MHz Frequency Response

• Small, Low-Profile Surface Mount Packages

Applications:

• General Differential Field Sensing

• Gear Tooth and Encoder Speed and Position Sensing

• Low Power, Low Voltage Applications

Description:

The AB-Series GMR sensors are general-purpose gradiometers for use in a wide variety of applications. Two pairs of unshielded GMR sensor elements provide for directional sensing of small gradients in large and small magnetic fields. The ability to detect only magnetic gradients allows low sensitivity to external sources of uniform magnetic field allowing these sensors to work successfully in high magnetic noise environments such as near electric motors or current carrying wires

.

V+ (supply)

Pinout

OUT B

Functional Block diagram

pin 8, V+(supply)

Y

GMR

X

X

NVE

ABxxx-02

Y pin 5, OUT B

Pin 1

OUT A V- (ground)

Axis of Sensitivity

Magnetic Characteristics:

Part

Number

Saturation

Field (Oe

1

)

X Y pin 4, V-

(ground) pin 1, OUT A

Linear

Range

(|Oe

1

|)

Resistor

Sensitivity

(%R / Oe

1

)

Resistance

(Ohms) Package

2

Min Max Min Max

Die Size

3

(

µ

m)

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General Characteristics:

Input Voltage Range

Operating Frequency

Operating Temperature Range

Bridge Electrical Offset

Signal Output at Max. Field

<1

4

DC

-50

-4

±12.5

4

>1

125

120

+4

Volts

MHz

°

C mV/V mV/V

AB Sensors

Off Axis Characteristic

ESD Tolerance

Notes:

% /

°

C

-0.1

Cos

β

7

400 V pin-to-pin HBM

1. 1 Oersted (Oe) = 1 Gauss in air.

2. See the Appendix for package dimensions and tolerances.

3. Sensors can be provided in die form by special request.

B-Series

sensors are pure ratiometric devices, meaning that they will operate properly at extremely low supply voltages

.

The output signal will be proportional to the supply voltage

.

Maximum voltage range is limited by the power dissipation in the package and the maximum operating temperature of the sensor.

5. Unipolar operation means exposure to magnetic fields of one polarity, e.g., 0 to 30 Gauss, or -2 to -50 Gauss, but not -20 to +30 Gauss (bipolar operation)

.

Bipolar operation will increase nonlinearity and hysteresis.

6. TCR is resistance change with temperature with no applied field

.

TCOI is the output change with temperature using a constant current source to power the sensor

.

TCOV is the output change with temperature using a constant voltage source to power the sensor.

-400

Typical Gradiometer Transfer Function

50

40

30

20

Increasing field on Y resistors

10

0

-10

0

-20

-30

Increasing field on X resistors

200 400

-40

-50

Magnetic Field Applied to Resistors

The Figure at left is a simulated output from an

NVE Gradiometer. The output / gradient correlation shown assumes one pair of resistors is held at zero field. Note the bipolar output.

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ABH Sensors

ABH Sensors

Features:

• Extremely High Sensitivity to Applied Magnetic Fields

• Wheatstone Bridge Analog Output

• Temperature Tolerance to 150°C Continuous

• Wide Linear Range of Operation

• Near-Zero Voltage Operation

• DC to >1MHz Frequency Response

• Small, Low-Profile Surface Mount Packages

Applications:

• General Differential Field Sensing

• Gear Tooth and Encoder Speed and Position Sensing

• Low Voltage, High Temperature Applications

Description:

The ABH-Series GMR sensors are low field, high temperature gradiometers for use in a wide variety of applications. Two pairs of unshielded GMR sensor elements provide for directional sensing of small gradients in large and small magnetic fields. The ability to detect only magnetic gradients allows low sensitivity to external sources of uniform magnetic field allowing these sensors to work successfully in high magnetic noise environments such as near electric motors or current carrying wires.

V+ (supply)

X

Pinout

NVE

ABxxx-02

OUT B

Y

Functional Block diagram

pin 8, V+(supply)

Y

GMR

X pin 5, OUT B

X Y pin 4, V-

(ground) pin 1, OUT A

Pin 1

OUT A V- (ground)

Axis of Sensitivity

Magnetic Characteristics:

Part

Number

Saturation

Field (Oe

1

)

Linear

Range

(|Oe

1

|)

Resistor

Sensitivity

(%R / Oe

1

)

Resistance

(Ohms) Package

2

Die Size

3

(

µ

m)

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General Characteristics:

Input Voltage Range

Operating Frequency

Operating Temperature Range

Bridge Electrical Offset

Signal Output at Max. Field

<1

4

DC

-50

-4

±6

4

>1

150

80

+4

Volts

MHz

°

C mV/V mV/V

ABH Sensors

Off Axis Characteristic

ESD Tolerance

Notes:

% /

°

C

0.0

Cos

β

7

400 V pin-to-pin HBM

1. 1 Oersted (Oe) = 1 Gauss in air.

2. See the Appendix for package dimensions and tolerances.

3. Sensors can be provided in die form by special request.

B-Series

sensors are pure ratiometric devices meaning that they will operate properly at extremely low supply voltages

.

The output signal will be proportional to the supply voltage

.

Maximum voltage range is limited by the power dissipation in the package and the maximum operating temperature of the sensor.

5. Unipolar operation means exposure to magnetic fields of one polarity, e.g., 0 to 30 Gauss, or -2 to -50 Gauss, but not -20 to

+30 Gauss (bipolar operation)

.

Bipolar operation will increase nonlinearity and hysteresis.

6. TCR is resistance change with temperature with no applied field

.

TCOI is the output change with temperature, using a constant current source to run the sensor

.

TCOV is the output change with temperature, using a constant voltage source to run the sensor.

-400

Typical Gradiometer Transfer Function

50

40

30

20

10

Increasing field on Y resistors

0

-10

0

-20

-30

-40

Increasing field on X resistors

200 400

-50

Magnetic Field Applied to Resistors

The Figure at left is a simulated output from an

NVE Gradiometer. The output / gradient correlation shown assumes one pair of resistors is held at zero field. Note the bipolar output.

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