ATS642LSHTN-I2-T Allegro Microsystems Inc, ATS642LSHTN-I2-T Datasheet - Page 13

• Manufacturer Part Number: ATS642LSHTN-I2-T
• Description: IC SENSOR GEAR TOOTH 4-SIP
• Manufacturer: Allegro Microsystems Inc
• Type: Special Purposer

Specifications of ATS642LSHTN-I2-T

• Output Type: Digital, Open Collector
• Sensing Range: 120mV Trip, 120mV Release
• Voltage - Supply: 4 V ~ 24 V
• Current - Supply: 8.4mA
• Features: Gear Tooth Type
• Operating Temperature: -40°C ~ 150°C
• Package / Case: 4-SIP
• Termination Type: Through Hole
• Bandwidth: 40kHz
• Current Rating: 16.8mA
• Operate Point Max: 1000G
• Supply Voltage Max: 24V
• Leaded Process Compatible: Yes
• No. Of Pins: 4
• Hall Effect Type: Gear Tooth
• Supply Voltage Min: 4V
• Rohs Compliant: Yes
• Filter Terminals: Through Hole
• Operate Point Min: 30G
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output (max): -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

ATS642LSH
Sensor Operation
Each operating mode is described in detail below.
Power-On
When power (V
period of time is required to power the various portions of the
IC. During this period, the ATS642 will power-on in the high
current state, I
could induce a change in the output state. Such an event could be
caused by thermal transients, but would require a static applied
magnetic field, proper signal polarity, and particular direction
and magnitude of internal signal drift.
Initial Offset Adjust
The sensor intially cancels the effects of chip, magnet, and
installation offsets. Once offsets have been cancelled, the digital
tracking DAC is ready to track the signal and provide output
switching. The period of time required for both Power-On and
Initial Offset Adjust is defined as the Power-On Time.
Calibration Mode
The calibration mode allows the sensor to automatically select
the proper signal gain and continue to adjust for offsets. The
Figure 9: Operation of Running Mode Gain Adjust.
Position 1. The device is initially powered-on. Self-calibration occurs.
Position 2. Small amplitude oscillation of the target sends an erroneously small differential signal to the sensor. The ampli-
tude of V
Position 3. The calibration period completes on the third rising output edge, and the device enters Running mode.
Position 4. True target rotation occurs and the correct magnetic signal is generated for the installation air gap. The estab-
lished signal gain is too large for the target’s rotational magnetic signal at the given air gap.
Position 5. Running Mode Calibration corrects the signal gain to an optimal level for the installation air gap.
Internal Differential
Signal, V
Sensor Electrical
Output, I
CC(High)
CC
> V
PROC
. After power on, there are conditions that
OUT
PROC
CCMIN
is greater than the switching hysteresis (B
) is applied to the device, a short
Peak-Detecting Gear Tooth Sensor with Continuous Calibration
1
2
B
OP
B
Two-Wire True Zero Speed Miniature Differential
RP
OP
and B
3
AGC is active, and selects the optimal signal gain based on the
amplitude of the V
the AGC DAC, the Offset DAC is also adjusted to ensure the
internal analog signal is properly centered.
During this mode, the tracking DAC is active and output switch-
ing occurs, but the duty cycle is not guaranteed to be within
specification.
Running Mode
After the Initial Calibration period, C
the device moves to Running mode. During Running mode, the
sensor tracks the input signal and gives an output edge for every
peak of the signal. AOA remains active to compensate for any
offset drift over time.
The ATS642 incorporates a novel algorithm for adjusting the
signal gain during Running mode. This algorithm is designed
to optimize the V
magnetic signal “seen” during the calibration period is not repre-
sentative of the amplitude of the magnetic signal for the installed
sensor air gap (see figure 9).
RP
), and the device output switches.
4
PROC
PROC
signal amplitude in instances where the
signal. Following each adjustment to
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Worcester, Massachusetts 01615-0036 U.S.A.
5
B
OP
B
RP
I
, establishes a signal gain,
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