Document
A1468
Three-Wire True Zero-Speed Differential Peak-Detecting Sensor IC with Continuous Calibration
FEATURES AND BENEFITS
• 4.0 to 26.5 V supply operating range • Minimum differential field 20 Gpk-pk • Running mode calibration for continuous optimization • Single chip IC for high reliability • Precise duty cycle signal throughout operating
temperature range • Large operating air gaps • Automatic Gain Control (AGC) for air-gap–independent
switchpoints • Automatic Offset Adjustment (AOA) for signal
processing optimization • True zero-speed operation • Undervoltage lockout • Reverse battery protection • Scan and IDDQ for increased test coverage
PACKAGE:
4-pin SIP (suffix K)
Not to scale
DESCRIPTION
TheA1468 is an optimized Hall-effect sensing IC that provides a user-friendly solution for digital ring-magnet sensing, or when coupled with a magnet, ferromagnetic target sensing, in three-wire applications. The small device package can be easily assembled into applications for use in conjunction with a wide variety of target shapes and sizes.
The integrated circuit incorporates dual Hall-effect elements with a 2.2 mm spacing and signal processing that switches in response to differential magnetic signals created by ringmagnet poles. The circuitry contains a sophisticated digital circuit to reduce system offsets, to calibrate the gain for airgap–independent switchpoints, and to achieve true zero-speed operation. Signal optimization occurs at power-on through the combination of offset and gain adjust, and is maintained throughout the operating time with the use of a running-mode calibration. The running-mode calibration provides immunity to environmental effects such as micro-oscillations of the target or sudden air gap changes.
The device is ideally suited to obtaining speed and duty cycle information in ring-magnet–based speed, position, and timing applications, such as in speedometers.
The A1468 is available in a 4-pin SIP (suffix K). The package is lead (Pb) free, with 100% matte-tin leadframe plating.
VCC
E1
Hall Amplifier
E2
Automatic Offset Adjustment (AOA)
Control
∑
AOA DAC
Gain
Internal Regulator
A1468-DS, Rev. 5 MCO-0000609
Automatic Gain Control (AGC)
AGC DAC
Test Signals TEST
Tracking DAC
Peak Hold
+ –
Functional Block Diagram
Current Limit
OUT
GND
February 22, 2019
A1468
Three-Wire True Zero-Speed Differential Peak-Detecting Sensor IC with Continuous Calibration
SELECTION GUIDE
Part Number
Package
A1468LK-T
4-pin through hole SIP
1 Contact Allegro™ for additional packing options.
Packing [1] Bulk, 500 pieces per bag
SPECIFICATIONS
ABSOLUTE MAXIMUM RATINGS
Characteristic
Symbol
Forward Supply Voltage Reverse Supply Voltage Output Current Reverse Output Current Reverse Output Voltage Output Off Voltage Operating Ambient Temperature Maximum Junction Temperature Storage Temperature
VCC VRCC IOUT IROUT VROUT VOUT
TA TJ(max)
Tstg
Notes Refer to Power Derating Curves chart
L temperature range
Operatin.