Self-Calibrating TPOS Gear Tooth Sensor Optimized

for Automotive Cam Sensing Applications

ATS673 and

ATS674

2

Allegro MicroSystems, Inc.

115 Northeast Cutoff, Box 15036

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

www.allegromicro.com

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.

▪ AGC and reference adjust circuit

▪ Undervoltage lockout

Features and Benefits (continued)

Description (continued)

Absolute Maximum Ratings

Characteristic

Symbol

Notes

Rating

Units

Supply Voltage

28

V

Reverse-Supply Voltage

–18

V

Continuous Output Current

20

mA

Reverse Output Current

50

mA

Operating Ambient Temperature

Range L

–40 to 150

ºC

Maximum Junction Temperature

165

ºC

Storage Temperature

–65 to 170

ºC

Terminal List

Name

Description

Number

VCC

Connects power supply to chip

1

VOUT

Device output

2

TEST

For Allegro use, float or tie to GND

3

GND

Ground terminal

4

24

3

1

Pin-out Diagram

Selection Guide

Part Number

Application

ATS673LSETN-LT-T

Yes

Low

High target wobble

13-in. reel, 450 pieces/reel

ATS673LSETN-HT-T

Yes

High

ATS674LSETN-LT-T

Yes

Low

High absolute edge detection accuracy

ATS674LSETN-HT-T

Yes

High

be NOT FOR NEW DESIGN. This classification indicates that sale of this device is currently restricted to existing customer applications. The device

should not be purchased for new design applications because obsolescence in the near future is probable. Samples are no longer available. Status

change: May 1, 2006. These variants include: ATS673LSETN-LT, ATS673LSETN-HT, ATS674LSETN-LT, and ATS674LSETN-HT.