Allegro MicroSystems ALS31300 3D Linear Hall-Effect Sensors offer 3DMAG™ technology and provide a 12-bit digital value corresponding to the magnetic field measured in each X, Y, and Z axes. The devices are preconfigured for 3D sensing applications for head-on linear motion, slide-by position sensing, and rotation angle measurements. The ALS31300 offers a joystick mode, including a low gain option for the Z-axis channel. This feature employs a back-bias magnet to permit return-to-zero force instead of traditional spring-based solutions. Three different factory-programmed sensitivity ranges are available in ±500G, ±1000G, and ±2000G.
The I2C address is set either by external resistors (16 unique addresses) or programmed into EEPROM via I2C (127 unique addresses), resulting in multiple devices on the same bus. Furthermore, the ALS31300 includes 78 bits of user EEPROM.
The ALS31300 enables robust joystick design, replacing potentiometer-based joystick modules. Magnetic joysticks can be low-profile, facilitating low system power for battery-powered applications and support joystick wake-on motion. With the addition of a back-bias magnet, the ALS31300 allows magnetic return to zero or removable joysticks.
Power management of the ALS31300 is highly configurable, allowing for system-level optimization of supply current and performance. Sleep mode consumes just 14nA (typical), making the ALS31300 appropriate for portable, battery-operated applications.
The ALS31300 is housed in a small footprint 3mm × 3mm × 0.8mm, 10-contact DFN package (“EJ”) that is lead (Pb) free, with 100% matte-tin lead-frame plating.
FEATURES
- X- and Y-axis sensing of joystick position
- Z-axis sensing of “crouch” or push-button motion
- Capable of operating with back-bias magnets for joystick return-to-zero
- Ideal for battery-powered, low-voltage applications
- 2.65V to 3.5V single supply operation
- 1MHz I2C compatibility down to 1.8V
- 14nA (typ) Sleep ICC
- 12μA to 2mA ICC (typ) in low-power duty cycle mode
- Industry-standard I2C interface for easy system integration
- Up to 1MHz (Fast Mode+) I2C communication
- 16 selectable addresses via an external resistor divider
- 127 available address configurable via EEPROM
- On-chip EEPROM
- Stores factory- and user-configured settings
- 78 bits of user EEPROM for additional storage
- On-chip charge pump for easy programming
- Flexible 12-bit ADC with 10-bit ENOB (Effective Number of Bits)
- 1% (typ) accurate factory-trimmed sensitivity options (±500G, ±1000G, and ±2000G full-scale input)
- Integrated temperature sensor
- Wide ambient temperature range of –40°C to 85°C
- 10-contact 3mm × 3mm × 0.8mm DFN package for implementation in low-profile, high-density PCB designs and space-constrained applications