AH1898-CA4-7 Diodes Incorporated

AH1898 PROGRAMMABLE MICROPOWER OMNIPOLAR HALL-EFFECT SWITCH Description Pin Assignments The AH1898 is a micropower magnetic range selectable (Bop/Brp) Omnipolar Hall effect switch IC with internal pull up and pull down capability, designed for portable and battery powered consumer equipment such as cellular phones and portable PCs. To support battery powered equipment and low voltage microcontrollers, the (Top View) (Bottom View) AH1898 can operate over the supply range of 1.6V to 3.6V and uses a hibernating clocking system to minimize the power consumption. The average supply current is only 4.3A typical at 1.80V. The AH1898 has an 8kV ESD rating on the supply and output pins. To minimize PCB space the AH1898 is packaged in the small CSP package (0.81mm x 0.81mm typical). The output is activated with either a north or south pole of sufficient magnetic field strength. The user can select one of two magnetic sensitivity bands via the BSEL pin without the addition of any external components allowing a flexible but small solution. The band select U-WLB0808-4 can be hardwired or be changed on the fly via a logic source such as a micro-controller. When the magnetic flux density (B) perpendicular to the package is larger than operate point (Bop), the output will be turned on (pulled low) and held until B is lower than release point (Brp). The output will remain off when there is no magnetic field. Applications Features Omnipolar Operation (North or South pole) Open and Close Detect for Cellular Phones Programmable Operate and Release Points Holster or Cover Detect for Cellular Phones and Tablet PCs Supply Voltage of 1.6V to 3.6V Cover or Display Switch in Portable PCs Micropower Operation Digital Still, Video Cameras and Handheld Gaming Consoles Chopper Stabilized Design Provides Proximity and Position Switches Superior Temperature Stability Minimal Switch Point Drift Enhanced Immunity to Physical Stress No External Pull-up Resistors Required Good RF Noise Immunity -40C to +85C Operating Temperature 8kV Human Body Model ESD Capability Miniature U-WLB0808-4 (CSP 0.81mm x 0.81mm typical) Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2) Halogen and Antimony Free. Green Device (Note 3) Notes: 1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant. 2. See AH1898 Typical Applications Circuit Note: 4. C is for power stabilization and to strengthen the noise immunity, the recommended capacitance is 100nF typical. IN Pin Descriptions Package: U-WLB0808-4 Pin Number Pin Name Function A1 BSEL Band Select Pin to select operating and release gauss points A2 GND Ground Pin B1 V Power Supply Input DD B2 OUTPUT Output Pin Functional Block Diagram 2 of 11 February 2013 AH1898 Diodes Incorporated www.diodes.com Document number: DS36028 Rev. 1 - 2 NEW PRODUCT