ATS673 and ATS674

ATS673LSE-DS

Worcester, Massachusetts 01615-0036 (508) 853-5000

115 Northeast Cutoff, Box 15036

www.allegromicro.com

Allegro MicroSystems, Inc.

ABSOLUTE MAXIMUM RATINGS

Operating Temperature

Tight timing accuracy over operating temperature range

True zero-speed operation

TPOS (True Power-On State)

Air-gap-independent switchpoints

High immunity to vibration

Large operating air gaps

Operation with supply voltages down to 3.3 V

Digital output representing target profile

Single-chip solution for high reliability

Optimized Hall IC/magnet system

AGC and reference adjust circuit

Undervoltage lockout

Recognizing the increasingly stringent requirements for EMC/EMI in automotive

applications, Allegro has taken the necessary steps to design devices that are

capable of withstanding the effects of radiated and conducted transients. The

ATS673 and ATS674 devices have been designed specifically for this purpose.

Advanced circuitry on the die allows them to survive positive and negative

transient pulses on both the input and output.

The ATS673 and ATS674 devices retain all of the same characteristics as the

ATS671 and ATS672. The devices remain true zero-speed gear tooth sensors with

optimized Hall IC/magnet configuration in an SIP (single in-line package). The

SIP assembly consists of a molded package that holds together a samarium cobalt

magnet, a pole piece, and a true zero-speed Hall IC that has been optimized to the

magnetic circuit.

The sensor incorporates a single element Hall IC that switches in response to

magnetic signals created by a ferrous target. The IC contains a sophisticated

digital circuit designed to eliminate the detrimental effects of magnet and system

offsets. Signal processing is used to provide zero-speed performance independent

of air gap and also to dynamically adapt device performance to the typical

operating conditions found in automotive applications, particularly cam sensing

applications (reduced vibration sensitivity).

High-resolution (9-bit) peak detecting DACs are used to set the adaptive switching

thresholds of the devices, ensuring high accuracy even in the presence of gear

eccentricity. Hysteresis in the thresholds reduces the negative effects of anomalies

in the magnetic signal (such as magnetic overshoot) associated with the targets

used in many automotive applications. The ATS673 and 674 also include a low

bandwidth filter that increases the noise immunity and the signal to noise ratio of

the sensor.

Two options are available for output polarity, low over tooth (LT) and high over

tooth (HT). For applications requiring absolute accuracy use the ATS674. The

ATS673 should be used for targets with high wobble.

Self-Calibrating TPOS Gear Tooth Sensor Optimized for

Automotive Cam Sensing Applications

Features and Benefits

Package SE, 4-pin Through Hole

1. VCC

2. VOUT

3. TEST

4. GND

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