HMC1042L-TR - Honeywell - Product.Network

2-Axis Magnetic Sensor

HMC1042L

The Honeywell HMC1042L is a high-performance, two-axis

magneto-resistive sensor. It is designed for magnetic compass

applications with capability of 0.2 degree accuracy. Stand alone or

by adding the companion HMC1041Z sensor, precision two and

three-axis magnetometry or compassing solutions are enabled. Pin

compatible with the HMC1052L; this miniature, low cost solution is

easy to assemble for high volume, cost effective OEM designs.

Applications for the HMC1042L include Compassing, Navigation

Systems, Magnetometry, and Magnetic Anomaly Detection.

The HMC1042L utilizes Honeywell’s Anisotropic Magnetoresistive

(AMR) technology that provides advantages over coil based

magnetic sensors. They are extremely sensitive, low field, low hysteresis, solid-state magnetic sensors designed to

measure direction and magnitude of Earth’s magnetic fields, from tens of micro-gauss to 6 gauss. Honeywell’s Magnetic

Sensors are among the most sensitive and reliable low-fiel d sensors in the industry.

Honeywell continues to maintain product excellence and performance by introducing innovative solid-state magnetic

sensor solutions. These are highly reliable, top performance products that are delivered when promised. Honeywell’s

magnetic sensor solutions provide real solutions you can co unt on.

FEATURES BENEFITS

4Two-Axis Precision Sensors 4Near-Perfect Orthogonality and ±0.2%FS/gauss Cross Axis

Performance

4Miniature Surface Mount Two-Axis

Magnetic Sensors (3mm x 3mm QFN) 4Small Size for Low Profile Sensing Applications and Mounting,

Compatible with High Speed SMT Assembly

4Low Voltage Operations (1.8V) 4Compatible for Battery Powered Applications

4Low Cost 4Designed for High Volume, Cost Effective OEM Designs

4Available in Tape & Reel Packaging 4High Volume OEM Assembly

4Lead Free Package Construction 4Complies with Current Environmental Standards

44-Element Wheatstone Bridge 4Low Noise Passive Element Design

4Wide Magnetic Field Range (+/-6 Oe) 4Sensor Can Be Used in Strong Magn etic Field Environments

4Patented Offset and Set/Reset Straps 4Stray Magnetic Field Compensation

HMC1042L

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SPECIFICATIONS

Characteristics Conditions* Min Typ Max Units

Bridge Elements

Supply Vbridge referenced to GND 1.8 3.0 20 Volts

Resistance Bridge current = 1mA 800 1000 1500 ohms

Field Range Full scale (FS) – total applied field -6 +6 gau ss

Sensitivity Set/Reset Current = 0.5A 0.8 1.0 1.2 mV/V/gauss

Resolution 1 kHz bandwidth, Vbridge = 5.0 volts 0.16

1.44 milli-gauss (RMS)

milli-gauss (pk – pk)

Bridge Offset Offset = (OUT+) – (OUT-)

Field = 0 gauss after Set pulse -1.25 ±0.5 +1.25 mV/V

Bandwidth Magnetic signal (lower limit = DC) 5 MHz

Disturbing Field Sensitivity starts to degrade.

Use S/R pulse to restore sensitivity. 20 gauss

Max. Exposed Field No perming effect on zero reading 10000 gauss

Operating Temperature Ambient -40 125 °C

Storage Temperature Ambient, unbiased -55 150 °C

Humidity Tested at 85°C 85 %

Sensitivity Tempco TA= -40 to 125°C, Vbridge=5V -3000 -2700 -2400 ppm/°C

Bridge Offset Tempco TA= -40 to 125°C, No Set/Reset

TA= -40 to 125°C, With Set/Reset ±500

±10 ppm/°C

Bridge Ohmic Tempco Vbridge=5V, TA= -40 to 125°C 2100 2500 2900 ppm/°C

Cross-Axis Sensitivity Cross field = 0.5 gauss, Happlied = ±3 gau ss ±0.2% %FS/gauss

Linearity Error Best fit straight line

± 1 gauss

± 3 gauss

± 6 gauss

0.1

0.5

1.8

%FS

Hysteresis Error 3 sweeps across ±3 gauss 0.06 %FS

Repeatability Error 3 sweeps across ±3 gauss 0.1 %FS

Weight 23.4 milli-grams

Set/Reset Strap

Resistance Measured from S/R+ to S/R- 3 4.5 6 ohms

Current 0.1% duty cycle, or less, 2µsec current puls e 0.4 0.5 4 Amp

Resistance Tempco TA=-40 to 125°C 3300 3700 4100 ppm/°C

Offset Straps

Resistance Measured from OFFSET+ to OFFSET- 12 15 18 ohms

Offset Constant DC Current, Field applied in sensitive direction 10 mA/gauss

Resistance Tempco TA=-40 to 125°C 3500 3900 4300 ppm/°C

* Tested at 25°C except stated otherwise.

HMC1042L

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SCHEMATIC DIAGRAM

PIN CONFIGURATIONS

(Arrow indicates direction of applied field that generates a positive output voltage after a SET pulse.)

Pin Number Function

1 GND2 (A)

2 OFF+

3 OUT+ (A)

4 VB

5 NC

6 OFF-

7 GND2 (B)

8 S/R+

9 NC

10 OUT- (B)

11 S/R-

12 NC

13 GND1 (A)

14 OUT- (A)

15 GND1 (B)

16 OUT+ (B)

GND1

(A) GND1

(B)

OUT-

(A) OUT+

(A) OUT-

(B) OUT+

(B)

OFF-

(A,B) OFF+

(A,B) S/R-

(A,B) S/R+

(A,B)

GND2

(A) GND2

(B)

GND1

(A) GND1

(B)

OUT-

(A) OUT+

(A) OUT-

(B) OUT+

(B)

OFF-

(A,B) OFF+

(A,B) S/R-

(A,B) S/R+

(A,B)

GND2

(A) GND2

(B)

1234

9101112

GND2

(A)

OFF+

OUT+

(A)

OFF-

GND2

(B)

S/R+

OUT-

(B) S/R- NC

GND1

(A)

OUT-

(A)

GND1

(B)

OUT+

(B)

BOT TOM VIEW

1234

9101112

GND2

(A)

OFF+

OUT+

(A)

OFF-

GND2

(B)

S/R+

OUT-

(B) S/R- NC

GND1

(A)

OUT-

(A)

GND1

(B)

OUT+

(B)

BOT TOM VIEW

HMC1042L

4 www.honeywell.com

PACKAGE OUTLINES

PACKAGE DRAWING HMC1042L (16-PIN LCC, dimensions in millimeters)

The following is the recomm end printed circuit board (PCB) footprint for the HMC1042 L. All dimensions are nominal and

in millimeters.

Millimeters Symbol min max

A 0.80 1.00

A1 0 0.05

A3 0.20 REF

b 0.18 0.30

D 3.00 BSC

D2 1.55 1.80

E 3.00 BSC

E2 1.55 1.80

e 0.50 BSC

L 0.30 0.50

N 16

ND 4

NE 4

r B(min)/2

aaa 0.15

bbb 0.10

ccc 0.10

NOMINAL PAD SIZE 0.40 X 0.23 MM

NOMINAL LAND SIZE 0.65 X 0.28 MM

0.20

0.05

NOMINAL PAD SIZE 0.40 X 0.23 MM

NOMINAL LAND SIZE 0.65 X 0.28 MM

0.20

0.05

HMC1042L

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Stencil Design and Solder Paste

A 4 mil stencil and 100% paste coverage is re commended for the electrical contact pads. The HMC1042L has b een

tested successfully with no-clean solder paste.

BASIC DEVICE OPERATION

The Honeywell HMC1042L magnetoresistive sensors are Wheatstone bridge devices to measure magnetic fields. With

power supply applied to the bridges, the sensors convert any incident magnetic field in the sensitive axis directions to a

differential voltage output. In addition to the bridge circuit, the sensor has two on-chip magnetically coupled straps; the

offset strap and the set/reset strap. These straps are Honeywell patented features for incident field adjustment and

magnetic domain alignment; and eliminate the need for external coils positioned around the sensors. The straps are

common in effect to both bridges.

The magnetoresistive sensors are made of a nickel-iron (Permalloy) thin-film deposited on a silicon wafer and patterned

as a resistive strip element. In the presence of a magnetic field, a change in the bridge resistive elements causes a

corresponding change in v oltage across the bridge outputs.

These resistive elements are aligned together to have a common sensitive axis (indicated by arrows on the pinouts) that

will provide positive voltage change with magnetic fields increasing in the sensitive direction. Because the output only is in

proportion to the one-dimensional axis (the principle of anisotropy) and its magnitude, additional sensor bridges placed at

orthogonal directions permit accurate measurement of arbitrary field direction. The combination of sensor bridges in two

and three orthogonal axis permit applications such as compassing and magnetometry.

The offset strap allows for several modes of operation when a direct current is driven through it. These modes are: 1)

Subtraction (bucking) of an unwanted external magnetic field, 2) null-ing of the bridge offset voltage, 3) Closed loop field

cancellation, and 4) Auto-calibration of bridge gain.

The set/reset strap can be pulsed with high currents for the following benefits: 1) Enable the sensor to perform high

sensitivity measurements, 2) Flip the polarity of the bridge output voltage, and 3) Periodically used to improve linearity,

lower cross-axis effects, and temperature effects.

Offset Strap

The offset strap is a spiral of metallization that couples in the sensor element’s sensitive axis. The offset strap measures

nominally 15 ohms, and requires 10mA for each gauss of induced field. The straps will easily handle currents to buck or

boost fields through the ±6 gauss linear measurement range, but designers should note the extreme thermal heating on

the die when doing so.

With most applications, the offset strap is not utilized and can be ignored. Designers can leave one or both strap

connections (Off- and Off+) open circuited, or ground one connection node. Do not tie both strap connections together to

avoid shorted turn magnetic circuits.

Set/Reset Strap

The set/reset strap is another spiral of metallization that couples to the sensor elements easy axis (perpendicular to the

sensitive axis on the sensor die. Each set/reset strap has a nominal resistance of 4.5 ohms with a nominal required peak

current of 500mA for reset or set pulses. With rare exception, the set/reset strap must be used to periodically condition the

magnetic domains of the magneto-resi stive elements for best and reliable performance.

A set pulse is defined as a positive pulse current entering the S/R+ strap connection. The successful result would be the

magnetic domains aligned in a forward easy-axis direction so that the sensor bridge’s polarity is a positive slope with

positive fields on the sensitive axis result in positive voltages across the bridge output conn ections.

A reset pulse is defined as a negative pulse current entering the S/R+ strap connection. The successful result would be

the magnetic domains aligned in a reverse easy-axis direction so that bridge’s polarity is a negative slope with positive

fields on the sensitive axis result in negative voltages across the bridge output connections.

Typically a reset pulse is sent first, followed by a set pulse a few milliseconds later. By shoving the magnetic domains in

completely opposite directions, any prior magnetic disturbances are likely to be completely erased by the duet of pulses.

For simpler circuits with less critical requirements for noise and accuracy, a single polarity pulse circuit may be employed

HMC1042L

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(all sets or all resets). With these uni-polar pulses, several pulses together become close in performance to a set/reset

pulse circuit. Figure 1 shows a quick and dirty manual pulse circuit for uni-polar application of pulses to the set/re set stra p.

ORDERING INFORMATION

Ordering Number Product

HMC1042L

HMC1042L T/R 3k

HMC1042L Cut Tape

Two Axis Magnetic Sensor

Tape and Reel 3k pieces/reel

Cut Tape

FIND OUT MORE

For more information on Honeywell’s Magneti c Sensors visit u s on line at www.magneticsensors.com or contact us at

800-323-8295 (763-9 54-2474 internationally).

The application circuits herein constitute typical usage and interface of Honeywell pro duct. Honeywell does not warranty or assume liability of customer-

designed circuits derived from this description or depiction.

Honeywell reserves the right to make changes to improve reliability, function or design. Honeywell does not assume any liability arising out of the

application or use of any product or circuit described herein; neither does it convey any license under its patent rights nor the rights of others.

U.S. Patents 4,441,072, 4,533,872, 4,569,742, 4,681,812, 4,847,584 and 6,529,114 apply to the technology described

Iset

5 volts

Rsr

3.0

Iset

5 volts

Rsr

3.0

Honeywell

12001 High wa y 55

Plymouth, MN 55441

Tel: 800-323-8295

www.honeywell.com/magneticsensors

Form #900340

November 2006

well International Inc.

Figure 1

Manual Set Pulse Circuit