ATS612LSB Allegro Microsystems Inc, ATS612LSB Datasheet - Page 9

• Manufacturer Part Number: ATS612LSB
• Description: IC SENSOR GEAR TOOTH 4LEAD
• Manufacturer: Allegro Microsystems Inc
• Type: Special Purposer

Specifications of ATS612LSB

• Sensing Range: *
• Voltage - Supply: 3.6 V ~ 24 V
• Current - Supply: 15mA
• Current - Output (max): 55mA
• Output Type: Digital, Open Collector
• Features: Gear Tooth Type
• Operating Temperature: -40°C ~ 150°C
• Package / Case: 4-SIP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

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IC/pellet configuration that is fully optimized to provide
digital detection of gear-tooth edges in a small package
size. This device contains self-calibrating circuitry that
nulls out the effect of air gap variations on the switching
accuracy of the device. A high startup hysteresis mini-
mizes false switching caused by magnetic overshoot. The
device is packaged in a miniature plastic housing that has
been optimized for size, ease of assembly, and
manufacturability. High operating temperature materials
are used in all aspects of construction.
is applied to the component, it is capable of instantly
providing digital information that is representative of the
profile of a rotating gear. No additional optimization or
processing circuitry is required. This ease of use should
reduce design time and incremental assembly costs for
most applications.
Hall Technology . This ATS612 package
contains a single-chip differential Hall-effect sensor IC, a
samarium-cobalt pellet, and a flat ferrous pole piece.
The Hall IC consists of two Hall elements located so as to
measure the magnetic gradient created by the passing of a
ferrous object (a gear). The two elements measure the
field gradient and convert it to voltage which is then
subtracted and processed in order to provide a digital
output signal.
tion scheme to eliminate magnet and system offsets. This
technique allows dynamic coupling and filtering of offsets
without the power-up and settling time disadvantages of
classical high-pass filtering schemes. The peak signal of
every tooth and valley is detected by the filter and is used
to provide an instant reference for the operate and release
point comparator. In this manner, the thresholds are
adapted and referenced to individual signal peaks and
valleys, hence providing immunity to zero line variation
due to installation inaccuracies (tilt, rotation, and off center
placement), as well as for variations caused by target and
shaft eccentricities. The peak detection concept also
allows extremely low speed operation for small value filter
capacitors.
ATS612LSB
DYNAMIC, SELF-CALIBRATING, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT GEAR-TOOTH SENSOR IC
The ATS612LSB gear-tooth sensor IC is a Hall
The use of this device is simple; after correct power
The processing circuit uses a patented peak detec-
DEVICE DESCRIPTION
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]
circuitry that is engaged at power on. The signal ampli-
tude is measured and the device gain is normalized. In
this manner, switch-point drift versus air gap is minimized
and excellent timing accuracy can be achieved. The AGC
circuitry, in conjunction with a unique hysteresis circuit,
also eliminates the effect of gear edge overshoot as well
as increases the immunity to false switching caused by
gear tooth anomalies at close air gap. The AGC circuit
sets the gain of the device after power on. Up to 0.25 mm
air gap change can occur after calibration is complete
without significant performance impact.
Superior Performance. The ATS612LSB peak-detecting
differential gear-tooth sensor IC has several advan-
tages over conventional Hall-effect gear-tooth sensors.
The signal-processing techniques used in the ATS612LSB
peak-detecting differential gear-tooth sensor IC solve the
catastrophic issues that affect the functionality of conven-
tional digital gear-tooth sensors.
• Temperature drift. Changes in temperature do not
• Timing accuracy variation due to air gap. The
• Dual edge detection. Because this device switches
greatly affect this device due to the stable amplifier
design and the offset rejection circuitry.
accuracy variation caused by air gap changes is
minimized by the self calibration circuitry. A 2x-to-3x
improvement can be seen.
from the positive and negative peaks of the signal, dual
edge detection is guaranteed.
V
OUT(SAT)
The ATS612LSB also includes self-calibration
V
BB
0
OPERATE
RELEASE
OPERATE
Dwg. WH-011
RELEASE