Allegro MicroSystems A1425
The A1425 AC-coupled Hall-effect sensor IC is a monolithic integrated circuit that switches in response to changing differential magnetic fields created by rotating ring magnets and, when coupled with a magnet, by ferrous targets. The device is a true zero-crossing detector: the output switches precisely when the difference in magnetic field strength between the two Hall elements is zero. The zerocrossing nature of this device provides excellent repeatability and accuracy for crankshaft applications.| Part No. | A1425 |
|---|---|
| Datasheet | A1425 Download |
| Manufacturer |  Allegro MicroSystems |
| Description | High Accuracy Analog Speed Sensor |
| Buy | Stock & Price |
FEATURES AND BENEFITS
● Used in sensing motion of ring magnet or ferrous targets● Integrated filter capacitor
● Wide operating temperature range
● Operation with magnetic input signal frequency from 20 Hz to 20 kHz
● Resistant to EMI
● Large effective air gaps
● 4.0 to 26.5 V supply operating range
● Output compatible with both TTL and CMOS logic families
● Reverse battery protection
● Resistant to mechanical and thermal stress
● Accurate true zero-crossing switch point PACKAGE: 4 pin SIP (suffix K)
DESCRIPTION
A unique dual-comparator scheme provides for accurate switching at the zero crossing on both the positive and negative-going regions of the differential signal, while utilizing hysteresis to prevent false switching. Changes in field strength at the device face, which are induced by a moving target, are sensed by the two integrated Hall transducers. The transducers generate signals that are differentially amplified by on-chip electronics. This differential design provides immunity to radial vibration within the operating air gap range of the A1425, by rejection of the common mode signal.
