US5781LSE Melexis Inc, US5781LSE Datasheet - Page 40

• Manufacturer Part Number: US5781LSE
• Description: IC HALL EFFECT SWITCH TSOT-23
• Manufacturer: Melexis Inc
• Type: Unipolar Switchr

Specifications of US5781LSE

• Sensing Range: 15mT Trip, 3.5mT Release
• Voltage - Supply: 3.5 V ~ 24 V
• Current - Supply: 5mA
• Current - Output (max): 50mA
• Output Type: Digital, Open Drain
• Operating Temperature: -40°C ~ 150°C
• Package / Case: SOT-23
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -
• Other names: US5781LSETR

Programmable Motion Sensors
The use of Hall-Effect Sensors as an alternative to resistive potentiometers is a popular trend because of
the advantages of non-contacting elements. in the past, linear Hall ICs were not very practical because of
bad temperature prformance and the ned for disctete trimming methods.
Melexis created it’s programmable linear Hall ICs to solve both problems, leaving the end-user a very
accurate sensor which is stable over temperature.
The configurations are infinite, shown are two basic magntic circuits which will allow literally thousands
of position sensing applications.
Rotary Motion
Figure 27 is the rotary method, where the Hall Ic is placed within a ring magnet, and the manetic field is
linear to the rotary motion. Depending on the magnetic elements, this method can be linear up to 160
typically, as shown 45
position application.
Linear Motion
Figure 28 illustrates a linear position sensor, where a linear motion (as apposed to rotary motion) is trans-
lated to a liear voltage via the Hall IC. The magnetic circuit shown is linear for approximately 50% of the
entire length of magnet. For example, if the magnets were 1” long, they can be used to measure 1/2” of
motion.
Programming
To further enhance the system, the sensors are programmable to give optimal results. Details about pro-
gramming are available in the MLX90215 and MLX90237 datasheets in section 4 of this book
Figure 27, Programmable Rotary Potentiometer
o
-90
o
of linearity can be easily achieved. This configuration is suitable for any rotary
3-25
N
S
Section 3 - Applications
PTC
TM
o
, but