SS248

CMOS Omnipolar High Sensitivity Micropower Hall Switch

1

V2.00

May 1, 2012

Features



Micropower consumption for battery powered applications



Omnipolar, output switches with absolute value of North or South pole from magnet



Operation down to 2.5V



High sensitivity for direct reed switch replacement applications

3 pin SOT23 (suffix SO)

3 pin SIP (suffix UA)

General Description

The S248 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 S248 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.

Applications



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