Magnetoresistive Sensor ICs

Nanopower Series

Datasheet

Magnetoresistive Sensor ICs

Honeywell’s Nanopower Series Magnetoresistive (MR) Sensor ICs are ultra-sensitive devices designed to accommodate a wide range of applications with large air gaps, small magnetic fields and low power requirements.

The sensor ICs respond to either a North or South pole applied in a direction parallel to the sensor. They do not require the magnet polarity to be identified, simplifying installation and potentially reducing system cost.

These sensor ICs use a very low average current consumption and a push-pull output which does not require a pull-up resistor. The sensor ICs can operate from a supply voltage as low as 1.65 V, promoting energy efficiency.

The Nanopower Series is available in two magnetic sensitivities to accommodate a variety of application needs:

• SM351LT: For applications requiring ultra high magnetic sensitivity (7 G typical operate, 11 G maximum operate) and a

very low current draw (360 nA typical).

• SM353LT: For applications requiring very high magnetic sensitivity (14 G typical operate, 20 G maximum operate) and

a very low current draw (310 nA typical).

These Magnetoresistive Sensor ICs, Nanopower Series, are supplied in the subminiature SOT-23 surface mount package on tape and reel (3000 units per reel), for use in automated pick-and-place component installation.

Key Features

• High sensitivity: 7 Gauss typ., 11 Gauss max. (SM351LT);

14 G typ., 20 Gauss max. (SM353LT)

• Nanopower: Average current of 360 nA typ. (SM351LT) and

310 nA typ. (SM353LT)

• Supply voltage range: 1.65 Vdc to 5.5 Vdc; simplifies design-in

• Omnipolar sensing: Activates with either pole from a magnet

• Temperature range: -40 °C to 85 °C [-40 °F to 185 °F]

• Push-pull output: Does not require external pull-up resistor

• Non-chopper stabilized design

• RoHS-compliant materials: Meets Directive 2002/95/EC

• Package: SOT-23

Potential Applications

INduSTRIaL

• Mobile equipment (i.e., handheld computing equipment, scanners)

• Water, electric and gas utility meters

• Building access control; reed switch replacement for batteryoperated security systems

• Industrial smoke detectors

MEdICaL

• Exercise equipment

• Infusion pumps

• Drawer position sensing (e.g., medical cabinets)

• Hospital beds

WHITE GOOdS

• Lid, door and drawer position detection

• Fluid flow

MEdIuM-SIZEd CONSuMER ELECTRONICS

• Battery-optimization position sensor

2 sensing.honeywell.com

HIGH SENSITIVITy • NANOPOWEr

Magnetoresistive Sensor ICs, Nanopower Series

Table 1a. Electrical Specifications (Vs = 1.65 V to 5.5 V, Ta = -40 °C to 85 °C [-40 °F to 185 °F], Typ. at 1.8 V, 25 °C [77 °F] unless otherwise specified.)

Characteristic Condition Min.

Typ.

Max.

unit

Vs reference to ground 1.65

1.8

5.5

V Supply voltage (Vs)

Awake current:

SM351LT

SM353LT

Awake time

Sleep current

—

—

—

Vs = 1.65 V

Vs = 1.8 V

Vs = 5.5 Vdc

—

—

0.3

—

—

—

—

—

30

1

0.8

15

0.2

0.16

0.2

2.6

100

5

5

—

8

0.8

1

8

180 mA

µs

µA ms Sleep time

Average current:

SM351LT

SM353LT

0.015% duty cycle, typ.

—

—

360

310

6640

6350 nA

Output voltage:

low (V

OL

)

high (V

OH

) load current = 100 µA 0

Vs - 0.15

0.03

Vs - 0.03

0.15

Vs

V

Table 1B. Electrical Specifications (Vs = 1.8 V, Ta = 25 °C [77 °F].)

Characteristic Condition

Awake current:

SM351LT

SM353LT

—

Awake time

Sleep current

Sleep time

Average current:

SM351LT

SM353LT

—

—

—

0.015% duty cycle, typ.

Min.

—

—

—

—

90

—

—

Typ.

1

0.8

15

0.2

100

350

350

Max.

1.12

0.87

—

0.59

120

620

600 unit mA

µs

µA ms nA sensing.honeywell.com

3

Magnetoresistive Sensor ICs, Nanopower Series

Table 2. Magnetic Specifications (Vs = 1.65 V to 5.5 V, Ta = -40 °C to 85 °C [-40 °F to 185 °F].)

Characteristic Min.

Typ.

Max.

SM351LT:

operate (positive)

release (positive)

hysteresis *

3

2

7

5

2

11

—

— unit

Gauss

SM353LT:

operate (positive)

release (positive)

hysteresis

NOTICE

*

6

3

*At 1.65 V and -40 °C, the hysteresis can reach 0.1 Gauss.

The magnetic field strength (Gauss) required to cause the switch to change state (operate and release) will be as specified in the magnetic characteristics. To test the switch against the specified magnetic characteristics, the switch must be placed in a uniform magnetic field.

14

10

4

20

—

—

Gauss

NOTICE

These magnetoresistive sensor ICs may have an initial output in either the ON or OFF state if powered up with an applied magnetic field in the differential zone (applied magnetic field >Brp and <Bop).

Honeywell recommends allowing 10 μs for output voltage to stabilize after supply voltage has reached its final rated value.

Table 3. absolute Maximum Ratings

Characteristic

Operating temperature

Soldering temperature

Supply voltage (Vs)

Output (load) current

Condition ambient ambient applied for <10 s

—

—

Min.

-40 [-40]

—

-0.5

—

NOTICE

Absolute maximum ratings are the extreme limits that the device will withstand without damage to the device.

However, the electrical and mechanical characteristics are not guaranteed as the maximum limits (above recommended operating conditions) are approached, nor will the device necessarily operate at absolute maximum ratings.

Typ.

—

—

—

100

Max.

85 [185]

265 [509]

5.5

150 unit

°C [°F]

°C [°F]

V

µA

Figure 1. Block/Electrical diagram

V

S+

Clock

Counter

Decoder

Gnd-

AMR

0

D

Dual

Threshold

Comparator

Output

Flip

Flop

Q Out

Magnetoresistive Sensor ICs, Nanopower Series

Figure 2. SM351LT Typical Performance Characteristics

Magnetic Performance vs Temperature (Vs = 1.8 V)

12

10

8

6

4

2

Operate Point

Release Point

60 80

Period vs Temperature

180

160

140

120

100

80

60

40

20

0

-40 -20

1.80 Vdc Supply

0

1.65 Vdc Supply

5.50 Vdc Supply

20

Temperature (°C)

40 60

0

-40 -20 0 20 40

Temperature (°C) average Current vs Temperature

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0.0

-40 -20

5.50 Vdc Supply

1.80 Vdc Supply

1.65 Vdc Supply

0 20

Temperature (°C)

40 60 80 active Mode Time vs Temperature

25

20

15

10

5

0

-40

1.80 Vdc Supply

-20

5.50 Vdc Supply

0 20

Temperature (°C)

40

1.65 Vdc Supply

60

80

80

Figure 3. SM353LT Typical Performance Characteristics

Magnetic Performance vs Temperature (Vs = 1.8 V)

20

18

16

14

12

10

8

6

4

2

0

-40

Operate Point

Release Point

-20 0 20

Temperature (°C)

40 average Current vs Temperature

3.5

5.50 Vdc Supply

3.0

2.5

2.0

1.5

1.0

0.5

0.0

-40 -20

1.80 Vdc Supply

1.65 Vdc Supply

0 20

Temperature (°C)

40

60

60

80

80

Period vs Temperature

160

140

120

100

80

60

40

20

0

-40 -20

1.80 Vdc Supply

1.65 Vdc Supply

5.50 Vdc Supply

0 20

Temperature (°C)

40 60 active Mode Time vs Temperature

25

80

20

15

10

5

0

-40

1.80 Vdc Supply

-20

5.50 Vdc Supply

0 20

Temperature (°C)

40

1.65 Vdc Supply

60 80 sensing.honeywell.com

5

Magnetoresistive Sensor ICs, Nanopower Series

Figure 4. Mounting and Tape/Reel dimensions (For reference only. mm/[in].) e

Sensor

2,90

[0.114]

3

GND

(-)

NOMINAL TO

IC CENTER

2,80

[0.110]

1,60

[0.063]

1

VCC

(+)

0,95

[0.037]

1,90

[0.075]

2

OUTPUT

3X 0,40 TYP.

[0.016]

1,45

[0.057]

1,20

[0.047]

0,77

[0.030]

NOMINAL TO

IC SENSING

SURFACE

0,413

[0.016]

0,60

[0.024]

0,787

[0.031]

Sensor Showing Polarity

0,13

[0.005]

1 or

6

6 1

0,20

[0.008]

4,00

[0.157]

2,00

[0.079]

4,00

[0.157]

1,50

[0.059]

Tape

1,75

[0.069]

3,50

[0.138]

8,00

[0.315]

Reel

0,061

[0.002]

TOP

COVER

TAPE

1,40

[0.055]

3,20

[0.125]

3,15

[0.124]

4,00

[0.157]

10,9

[0.429]

MEASURED

AT OUTER

EDGE

1,00

[0.039]

40,0

[1.57]

10

[0.394]

14,4

[0.567]

MEASURED

AT HUB

60,0

[2.362]

2,0

[0.079]

178 MAX.

[7.000]

20,2

[0.795]

MIN.

8,40

[0.331]

MEASURED

AT HUB

6 sensing.honeywell.com

13,0

[0.512]

Order Guide

Catalog Listing

SM351LT

SM353LT description

Magnetoresistive sensor IC, high sensitivity (7 G typ.), nanopower, SOT-23 package, tape and reel packaging (3000 units per reel)

Magnetoresistive sensor IC, high sensitivity (14 G typ.), nanopower, SOT-23 package, tape and reel packaging (3000 units per reel) addITIONaL INFORMaTION

The following associated literature is available at sensing.honeywell.com

:

• Product line guide

• Product range guide

• Product installation instructions

• Application note

WaRNING

PERSONaL INJuRY

DO NOT USE these products as safety or emergency stop devices or in any other application where failure of the product could result in personal injury.

Failure to comply with these instructions could result in death or serious injury.

WaRNING

MISuSE OF dOCuMENTaTION

• The information presented in this product sheet is for reference only. Do not use this document as a product installation guide.

• Complete installation, operation, and maintenance information is provided in the instructions supplied with each product.

Failure to comply with these instructions could result in death or serious injury.

Sales and Service

Honeywell serves its customers through a worldwide network of sales offices, representatives and distributors. For application assistance, current specifications, pricing or name of the nearest Authorized Distributor, contact your local sales office or email us at

[email protected]. Visit us on the Web at sensing.honeywell.com

Phone and Fax:

Asia Pacific +65 6355-2828

+65 6445-3033 Fax

Europe +44 (0) 1698 481481

+44 (0) 1698 481676 Fax

Latin America +1-305-805-8188

+1-305-883-8257 Fax

USA/Canada +1-800-537-6945

+1-815-235-6847

+1-815-235-6545 Fax

Sensing and Control

Honeywell

1985 Douglas Drive North

Golden Valley, MN 55422 honeywell.com

WaRRaNTY/REMEdY

Honeywell warrants goods of its manufacture as being free of defective materials and faulty workmanship. Honeywell’s standard product warranty applies unless agreed to otherwise by Honeywell in writing; please refer to your order acknowledgement or consult your local sales office for specific warranty details. If warranted goods are returned to Honeywell during the period of coverage,

Honeywell will repair or replace, at its option, without charge those items it finds defective. The foregoing is buyer’s sole remedy and is in lieu of all other warranties, expressed or implied, including those of merchantability and fitness for a particular purpose. In no event shall Honeywell be liable for consequential, special, or indirect damages.

While we provide application assistance personally, through our literature and the Honeywell website, it is up to the customer to determine the suitability of the product in the application.

Specifications may change without notice. The information we supply is believed to be accurate and reliable as of this printing.

However, we assume no responsibility for its use.

005966-1-EN

April 2014

© 2014 Honeywell International Inc. All rights reserved.