ASIL-Compliant Hall-Effect Wheel Speed Sensor IC

with Speed and Direction Output

A19300

12

Allegro MicroSystems

955 Perimeter Road

Manchester, NH 03103-3353 U.S.A.

www.allegromicro.com

ASIL Safe State Output Protocol

The A19300 sensor IC contains diagnostic circuitry that will

continuously monitor occurrences of failure defects within the IC.

Refer to Figure 10 for the output protocol of the ASIL safe state

after an internal defect has been detected. Error Protocol will

result from faults which cause incorrect signal transmission (i.e.,

too few or too many output pulses).

Note: If a fault exists continuously, the device will stay in perma-

nent safe state. Refer to the A19300 Safety Manual for additional

details on the ASIL Safe State Output Protocol.

N

S

N

Magne�c

Encoder

ICC(HIGH)

ICC(LOW)

ICC(HIGH)

ICC(LOW)

S

N

IRESET

tRESET

Normal

Opera�on

Error

Protocol

Error

TCAL

Figure 10: Output Protocol (ASIL Safe State)