US4881ESE Melexis Inc, US4881ESE Datasheet - Page 33

• Manufacturer Part Number: US4881ESE
• Description: IC HALL SW BIPO NORTH POLE SOT23
• Manufacturer: Melexis Inc
• Type: Bipolar Latchr

Specifications of US4881ESE

• Sensing Range: 6mT Trip, -6mT Release
• Voltage - Supply: 2.2 V ~ 18 V
• Current - Supply: 5mA
• Current - Output (max): 50mA
• Output Type: Digital, Open Drain
• Operating Temperature: -40°C ~ 85°C
• Package / Case: SOT-23
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -
• Other names: US4881ESETR

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