The SS340RT Series and SS440R Series sensors are small,
versatile digital Hall-effect devices that are operated by the
magnetic field from a permanent magnet or an electromagnet.
They are designed to respond to a single pole: North
(SS340RT Series) or South (SS440R Series).
These unipolar sensors are supplied in three different magnetic
sensitivities to meet a wide range of potential applications. The
SS341RT and SS441R offer the highest sensitivity, with a
typical operating point of 85 G at 25 °C [77 °F]; the SS343RT
and SS443R offer medium sensitivity with 125 G typical at
25 °C [77 °F]; the SS349RT and SS449R offer the lowest
sensitivity, requiring 350 G typical to operate at 25 °C [77 °F].
FEATURES/BENEFITS
•Subminiature package size (SS340RT Series) supplied on
tape and reel allows for a compact design with automated
component placement, helping to reduce manufacturing
costs
•Simple activation from a single pole and multiple magnetic
sensitivities (high, medium and low) make this product
suitable in a variety of potential motion control, lid closure
detection, and displacement sensing applications
•Low voltage 3 V capability helps reduce power
consumption
•Built-in reverse polarity protection protects the device from
potential damage during installation
•Thermally balanced integrated circuit provides for stable
operation over a wide temperature range, from -40 °C to
150 °C [-40 °F to 302 °F]
These sensors are available in two package styles. The
SS340RT Series is available in the miniature SOT-23 surface
mount package; the SS440R is available in the leaded, flat TO-
92-style package. The SS340RT’s small size requires less PC
board space, allowing it to be used in smaller assemblies. Its
3 V capability allows for use in low voltage applications,
promoting energy efficiency.
The SS340RT Series is available on tape and reel (3000 units
per reel); the SS440R Series is available in a bulk package
(1000 units per bag).
POTENTIAL APPLICATIONS
• Door or lid closure detection
• Speed and RPM (revolutions per minute) sensing in
fitness equipment
•Flow rate sensing in industrial processes, appliances, or
water softeners
•Damper or valve position control in industrial, HVAC or
residential or commercial applications
• Robotic control (cylinder position monitoring)
• Float-based fluid level sensing
• Displacement sensor in hospital beds or medical
equipment
• Medication bin monitor on portable drug carts
• Printer head position sensing
SS340RT and SS440R Series
Table 1. SS340RT and SS440R Series Specifications (At Vs=3.0 to 24 Vdc, 20 mA load, TA = -40 ºC to 150 ºC [-40 ºF to 257 ºF])
Characteristic Condition Minimum Typical Maximum Unit
Supply voltage:
SS440R Series -40 °C to 150 °C [-40 °F to 302 °F] 3 – 24
SS340RT Series -40 °C to 125 °C [-40 °F to 257 °F] 3 – 24
SS340RT Series 150 °C [302 °F] 3 – 12
Supply current Vsupply = 5 V at 25 °C [77 °F]
Vsat at 20 mA, gauss >Bop – – 0.4 Vdc
Output leakage current gauss >Bop – – 10 µA
Operating temperature – -40 [-40] – 150 [302] °C [°F]
Storage temperature – -40 [-40] – 150 [302] °C [°F]
Note 1. See Figure 1.
Table 2. SS340RT and SS440R Series Absolute Maximum Ratings
Characteristic Minimum Typical Maximum Unit
Supply voltage -28.0 – 28.0 V
Applied output voltage -0.5 – 28.0 V
Output current – – 20 mA
Magnetic flux – – no limit gauss
Note 1: 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.
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.
Figure 1. SS340RT Series Rated Supply VoltageFigure 2. Current Sinking Output Block Diagram
1
Vdc
Vsupply = 3 V at 25 °C [77 °F]
Vsupply = 12 V at 25 °C [77 °F],
=1.6 kOhm, CL = 20 pF
R
L
– –
–
–
–
–
–
4
3.5
–
–
–
6
5
mA
8
1.5
µs
1.5
– °C/W
303
–
gauss
240 350 460
–
gauss
135 250 370
–
gauss
30 100 170
1
2 www.honeywell.com/sensing
Figure 3. Wiring Diagrams
Unipolar Hall-Effect Digital Position Sensors
Figure 4. SS340RT Series Mounting/Tape and Reel Dimensions (For reference only. mm/[in])
Figure 5. SS440R Series Mounting Dimensions (For reference only. mm/[in])
Honeywell Sensing and Control 3
Order Guide
Catalog Listing Description
SS341RT SS340RT Series, unipolar, Hall-effect digital position sensor, high sensitivity, SOT-23 package, tape and
reel packaging (3000 units per reel)
SS343RT SS340RT Series, unipolar, Hall-effect digital position sensor, medium sensitivity, SOT-23 package, tape and
reel packaging (3000 units per reel)
SS349RT SS340RT Series, unipolar, Hall-effect digital position sensor, low sensitivity, SOT-23 package, tape and reel
packaging (3000 units per reel)
SS441R SS440R Series, unipolar, Hall-effect digital position sensor, high sensitivity, flat TO-92 package, bulk
packaging (1000 units per bag)
SS443R SS440R Series, unipolar, Hall-effect digital position sensor, medium sensitivity, flat TO-92 package, bulk
packaging (1000 units per bag)
SS449R SS440R Series, unipolar, Hall-effect digital position sensor, low sensitivity, flat TO-92 package, bulk
packaging (1000 units per bag)
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.
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 web site, 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.
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:
E-mail: info.sc@honeywell.com
Internet: www.honeywell.com/sensing
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