Diodes AH1898 User Manual
New prod uc t ah1898, Description, Features
AH1898
Document number: DS36028 Rev. 1 - 2
1 of 11
February 2013
© Diodes Incorporated
NEW PROD
UC
T
AH1898
PROGRAMMABLE MICROPOWER OMNIPOLAR HALL-EFFECT SWITCH
Description
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
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 4.3µA 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
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.
Features
Omnipolar Operation (North or South pole)
Programmable Operate and Release Points
Supply Voltage of 1.6V to 3.6V
Micropower
Operation
Chopper Stabilized Design Provides
Superior Temperature Stability
Minimal Switch Point Drift
Enhanced Immunity to Physical Stress
No External Pull-up Resistors Required
Good RF Noise Immunity
-40°C to +85°C 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)
Pin Assignments
(Top View) (Bottom View)
U-WLB0808-4
Applications
Open and Close Detect for Cellular Phones
Holster or Cover Detect for Cellular Phones and Tablet PCs
Cover or Display Switch in Portable PCs
Digital Still, Video Cameras and Handheld Gaming Consoles
Proximity and Position Switches
Notes:
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.
2. Se information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green" and Lead-free.
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl)
and <1000ppm antimony compounds.