SS256
CMOS Omnipolar High Sensitivity Micropower Hall Switch
Packages
Features and Benefits
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Operation down to 2.5V
Micropower consumption for battery
powered applications
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High sensitivity for direct reed switch
replacement applications
Omnipolar, output switches with absolute
value of North or South pole from magnet
3 pin SOT23 (suffix SO)
3 pin SIP (suffix UA)
Functional Block Diagram
Application Examples
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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
General Description:
The SS256 Omnipolar Hall effect sensor IC is fabricated from mixed signal CMOS technology. It incorporates
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 BOP/BRP 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 SS256 will be latched on (BOP) 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 (BRP) in the absence of a
magnetic field.
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V2.10 May 1, 2012
SECELECTRONICS [ SEC Electronics Inc. ]
