AH1897S HIGH SENSITIVITY MICROPOWER OMNIPLOAR HALL-EFFECT SWITCH Description Pin Assignments The AH1897S is a high sensitivity micropower Omnipolar Hall effect switch IC with an internal pull up and pull down capability. Designed for portable and battery powered equipment such as cellular phones and portable PCs, the average supply current is only 4.3A at 1.85V. To support portable equipment, the AH1897S can operate over the supply range of 1.6V to 3.6V and uses a hibernating clocking system to minimize the power consumption. To minimize PCB space, the AH1897S is available in a small low profile X1-DFN1216-4 (Type B) package. The output is activated with either a North or South pole of sufficient magnetic field strength. When the magnetic flux density (B) is X1-DFN1216-4 (Type B) perpendicular to the package is larger than operate point (Bop), the output will be turned on (pulled low). The output is turned off when B becomes lower than the release point (Brp). The output will remain off when there is no magnetic field. Applications Features Cover or Display Switch in Portable PCs Omnipolar Operation (North or South Pole) Open and Close Detect for Cellular Phones Supply Voltage of 1.6V to 3.6V Holster or Cover Detect for Cellular Phones and Tablet PCs Micropower Operation Digital Still, Video Cameras and Handheld Gaming Consoles Chopper Stabilized Design Provides: Contact-Less 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 Small Low Profile X1-DFN1216-4 (Type B) Package Moisture Sensitivity: Level 1 per J-STD-020 Terminals: Finish NiPdAu over Copper Leadframe, Solderable per MIL-STD-202, Method 208 Weight: 0.002 grams (Approximate) Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2) Halogen and Antimony Free. Green Device (Note 3 ) For automotive applications requiring specific change control (i.e. parts qualified to AEC-Q100/101/200, PPAP capable, and manufactured in IATF 16949 certified facilities), please contact us or your local Diodes representative. Offset Cancellation AH1897S Typical Applications Circuit 1.6V to 3.6V V DD OUTPUT C AH1897S IN GND Note: 4. C is for power stabilization and to strengthen the noise immunity, the recommended capacitance is 100nF typical. IN Pin Descriptions Package: X1-DFN1216-4 (Type B) without Center Exposed Pad Pin Number Pin Name Function 1 V Power Supply Input DD 2 GND Ground Pin 3 NC No Connection (Note 5) 4 OUTPUT Output Pin Note: 5. NC is No Connection pin and is not connected internally. This pin can be left open or tied to gro und. Functional Block Diagram V DD Sleep/Awake Logic and Power Switch Latch Hall Plate and Output Amp OUTPUT Driver Controller GND 2 of 8 AH1897S February 2020 Diodes Incorporated www.diodes.com Document number: DS37559 Rev. 2 - 2