SS239_1311 Datasheet, PDF (1/8 Pages) SEC Electronics Inc. – CMOS Omnipolar High Sensitivity Micropower Hall Switch

SS239
CMOS Omnipolar High Sensitivity Micropower Hall Switch
Packages
3 pin SOT23 (suffix SO)
3 pin SIP (suffix UA)
Features and Benefits
– Operation down to 2.5V
– Micropower consumption for battery
powered applications
– High sensitivity for direct reed switch
replacement applications
– Omnipolar, output switches with absolute
value of North or South pole from magnet
Functional Block Diagram
VDD
Sleep/Awake
Logic
Application Examples
OUT
– Solid-state switch
– Handheld Wireless Handset Awake Switch
– Lid close sensor for battery powered devices
– Magnet proximity sensor for reed switch
replacement in low duty cycle applications
Chopper
General Description
Hall
Plate
GND
The SS239 Omnipolar Hall effect sensor IC is fabri-
cated from mixed signal CMOS technology. It incor-
porates advanced chopper-stabilization techniques to
provide accurate and stable magnetic switch points.
The circuit design provides an internally controlled clocking mechanism to cycle power to the Hall element and
analog signal processing circuits. This serves to place the high current-consuming portions of the circuit into a
“Sleep” mode. Periodically the device is “Awakened” by this internal logic and the magnetic flux from the Hall
element is evaluated against the predefined thresholds. If the flux density is above or below the B_OP/B_RP thresholds
then the output transistor is driven to change states accordingly. While in the “Sleep” cycle the output transistor is
latched in its previous state. The design has been optimized for service in applications requiring extended operating
lifetime in battery powered systems.
The output transistor of the SS239 will be latched on (B_OP) in the presence of a sufficiently strong South or North
magnetic field facing the marked side of the package. The output will be latched off (B_RP) in the absence of a
magnetic field.
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V3.10 Nov 1, 2013