ATS616LSGTN-T Allegro Microsystems Inc, ATS616LSGTN-T Datasheet - Page 10

• Manufacturer Part Number: ATS616LSGTN-T
• Description: IC,HALL-EFFECT SWITCH,DIFFERENTIAL,BIPOLAR,SIP,4PIN,PLASTIC
• Manufacturer: Allegro Microsystems Inc
• Type: Special Purposer

Specifications of ATS616LSGTN-T

• Rohs Compliant: YES
• Sensing Range: 60G
• Voltage - Supply: 3.5 V ~ 24 V
• Current - Supply: 12mA
• 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: Lead free / RoHS Compliant
• Other names: 620-1116-2

ATS616LSG
AGC circuit sets the gain of the device after power-on. Up to a
0.25 mm air gap change can occur after calibration is complete
without significant performance impact.
Superior Performance.
over conventional Hall-effect devices. The signal-processing
techniques used in the ATS616 solve the catastrophic issues that
affect the functionality of conventional digital gear-tooth sen-
sors, such as the following:
• Temperature drift. Changes in temperature do not greatly
• Timing accuracy variation due to air gap. The accuracy varia-
• Dual edge detection. Because this device switches based on
• Tilted or off-center installation. Traditional differential sensor
• Large operating air gaps. Large operating air gaps are achiev-
• Immunity to magnetic overshoot. The patented adjustable
• Response to surface defects in the target. The gain-adjust
• Immunity to vibration and backlash. The gain-adjust circuitry
• Immunity to gear run out. The differential chip configuration
Differential vs. Single-Element Design.
configuration is superior in most applications to the classical
single-element design. The single-element configuration com-
affect this device due to the stable amplifier design and the
offset rejection circuitry.
tion caused by air gap changes is minimized by the self-cali-
bration circuitry. A 2×-to-3× improvement can be seen.
the positive and negative peaks of the signal, dual edge detec-
tion is guaranteed.
ICs can switch incorrectly due to baseline changes versus air
gap caused by tilted or off-center installation. The peak detec-
tor circuitry references the switchpoint from the peak and is
immune to this failure mode. There may be a timing accuracy
shift caused by this condition.
able with this device due to the sensitive switchpoints after
power-on (dependent on target dimensions, material, and
speed).
hysteresis circuit makes the ATS616 immune to switching on
magnetic overshoot within the specified air gap range.
circuitry reduces the effect of minor gear anomalies that would
normally cause false switching.
keeps the hysteresis of the device roughly proportional to the
peak-to-peak signal. This allows the device to have good im-
munity to vibration even when operating at close air gaps.
eliminates the baseline variations caused by gear run out.
The ATS616 has several advantages
Dynamic Self-Calibrating Peak-Detecting Differential
The differential chip
monly used (Hall-effect element mounted on the face of a simple
permanent magnet) requires the detection of a small signal (often
<100 G) that is superimposed on a large back-biased field, often
1500 G to 3500 G. For most gear/target configurations, the back-
biased field values change due to concentration effects, resulting
in a varying baseline with air gap, valley widths, eccentricities,
and vibration (figure 4). The differential configuration (figure 5)
cancels the effects of the back-biased field and avoids many of
the issues presented by the single Hall element design.
Peak Detecting vs. AC-Coupled Filters.
Figure 4. Affect of varying valley widths on single-element circuits.
Figure 4. Affect of varying air gaps on differential circuits.
Hall Effect Gear Tooth Sensor IC
115 Northeast Cutoff
1.508.853.5000; www.allegromicro.com
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 U.S.A.
High-pass filtering
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