ATS612LSB Allegro Microsystems Inc, ATS612LSB Datasheet - Page 15

• 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

Operation From a Regulated Power Supply. These
devices require minimal protection circuitry during opera-
tion from a low-voltage regulated line. The on-chip voltage
regulator provides immunity to power supply variations
between 3.6V and 24V. However, even while operating
from a regulated line, some supply and output filtering is
required to provide immunity to coupled and injected noise
on the supply line. A basic RC low-pass circuit (R
the supply line and an optional output capacitor (C
recommended for operation in noisy environments.
Because the device has an open-collector output, an
output pull-up resistor (R
IC output (pin 2) or by the signal processor input.
Operation From an Unregulated Power Supply. In
automotive applications, where the device receives its
power from an unregulated supply such as the battery, full
protection is generally required so that the device can
withstand the many supply-side transients. Specifications
for such transients vary between car manufacturers, and
protection-circuit design should be optimized for each
application. In the circuit below, a simple Zener-controlled
regulator is constructed using discrete components. The
RC low-pass filter on the supply line (R
value supply bypass capacitor (C
necessary, so as to minimize susceptibility to EMI/RFI.
The npn transistor should be chosen with sufficiently high
forward breakdown voltage so as to withstand supply-side
transients. The series diode should be chosen with
14
ATS612LSB
DYNAMIC, SELF-CALIBRATING, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT GEAR-TOOTH SENSOR IC
SUPPLY
20 Ω
R 1
R L
0.033 µF
C 1
Vcc
1
L
) must be included either at the
X
2
OUTPUT
APPLICATIONS INFORMATION — Continued
S
) can be included, if
3
X
0.22 µF
C 3
100 pF
C 2
+
-
1
4
C
Dwg. EH-008-1A
1
) and a low-
1
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]
2
C
) is
1
) on
sufficiently high reverse breakdown capabilities so as to
withstand the most negative transient. The current-limiting
resistor (R
power dissipation requirements.
Capacitor Requirements. The choice of the capacitor at
pin 3 (C
target. This capacitor (0.1 µF minimum) is required to
stabilize the internal amplifiers as well as to eliminate the
signal offsets. Typically, a 0.22 µF low-leakage ceramic
capacitor is recommended. Values greater than 0.47 µF
should not be used as this may cause high-speed perfor-
mance degradation.
dation in the low-speed performance of the device. Ex-
cess capacitor leakage can result in the IC changing
output state without movement of the gear tooth being
sensed. In addition to the capacitor leakage, it is ex-
tremely important to minimize the leakage at the PC board
and between the pins of the device. Up to 50nA of
external leakage can be tolerated at the capacitor pin node
to ground. Choice of low-leakage-current potting com-
pounds and the use of clean PC board techniques are
extremely important.
and other Hall-effect devices is provided in the Allegro
Integrated and Discrete Semiconductors Data Book or
Application Note 27701.
0.033 µF
SUPPLY
C S
Capacitor leakage current at pin 3 will cause degra-
Additional applications Information on gear-tooth
2.5 kΩ
R Z
3
) defines the minimum operating speed of the
Z
) and the Zener diode should be sized for
6.8 V
R L
20 Ω
R 1
0.033 µF
C 1
Vcc
1
X
2
OUTPUT
3
X
0.22 µF
C 3
100 pF
C 2
+
-
4
Dwg. EH-008A