US1881ESO Melexis Inc, US1881ESO Datasheet - Page 33
![IC LATCH CMOS MP SOT-23](/photos/19/50/195046/413-sot-23_sml.jpg)
US1881ESO
Manufacturer Part Number
US1881ESO
Description
IC LATCH CMOS MP SOT-23
Manufacturer
Melexis Inc
Type
Bipolar Latchr
Specifications of US1881ESO
Rohs Status
RoHS non-compliant
Sensing Range
9.5mT Trip, -9.5mT Release
Voltage - Supply
3.5 V ~ 24 V
Current - Supply
5mA
Current - Output (max)
50mA
Output Type
Digital, Open Drain
Operating Temperature
-40°C ~ 85°C
Package / Case
SOT-23
Features
-
Other names
US1881ESOTR
Flow Meter
One popular device that uses a Hall IC is a flow meter (Figure 15). The spoked wheel (paddle wheel), is
driven by some type of medium flowing through the pipe. A magnet is attached at the tip of each spoke.
In the presence of moving vapor or liquid, the magnets spin at a speed related to the viscosity of the medi-
um flowing through the device. The spinning magnets will switch the Hall IC, producing a square wave
output, with a frequency proportional to the flow rate.
Figure 19, Flow Meter
N
S
Liquid or vapor entering in the
direction of the arrow spins the
paddle wheel switching the Hall
IC “ON” and “OFF”, creating a
square wave output
.
Power Control
Many switches must control significant power. A Hall IC can do this only through a relay or Power FET.
For a component cost of $1.00, an isolated 50 Volt, 50 Amp switch can be made.
Figure 20, Power Switch
12V
Load
U18
627
Section 3 - Applications
3-19