Two-Wire True Zero-Speed Miniature Differential

Peak-Detecting Sensor IC with Continuous Calibration

A1642

10

Allegro MicroSystems, LLC

115 Northeast Cutoff

Worcester, Massachusetts 01615-0036 U.S.A.

1.508.853.5000; www.allegromicro.com

Power Supply Protection

The device contains an on-chip regulator and can operate over

unregulated power supply, transient protection must be added

externally. For applications using a regulated line, EMI/RFI pro-

tection may still be required. Contact Allegro Microsystems for

information on the circuitry needed for compliance with various

EMC specifications. Refer to figure 7 for an example of a basic

application circuit.

Undervoltage Lockout

When the supply voltage falls below the undervoltage lockout

Assembly Description

This device is integrally molded into a plastic body that has been

optimized for size, ease of assembly, and manufacturability.

High operating temperature materials are used in all aspects of

construction.

Diagnostics

The regulated current output is configured for two wire appli-

cations, requiring one less wire for operation than do switches

with the more traditional open-collector output. Additionally,

the system designer inherently gains diagnostics because there is

always output current flowing, which should be in either of two

current level not within these ranges indicates a fault condi-

general fault condition.

Figure 7: Typical Application Circuit

A1642

VCC

GND

V+

0.01

1

4

µF

ECU

Pins 2 and 3 floating

R

100

Ω

SENSE

Figure 8: Diagnostic Characteristics of Supply Current Values

0

+mA





Short

Fault

Open