HAR2425 datasheet(16/33 Pages) MICRONAS

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HAR 24xy

DATA SHEET

July 14, 2015; DSH000170_001EN

Micronas

3.3. On-Board Diagnostic Features

The HAR 24xy is made of two completely separated

dies, each featuring two groups of diagnostic functions.

The first group contains basic functions that are always

active. The second group can be activated by the cus-

tomer and contains supervision and self-tests related

to the signal path and sensor memory.

Table 3–4 describes the HAR 24xy overall behavior in

case of wiring faults.

Diagnostic Features that are Always Active:

– Wire break detection for supply and ground line

– Undervoltage detection

– Thermal supervision of output stage: overcurrent,

short circuit, etc. (HAR 2455)

Diagnostic Features that can be Activated by Cus-

tomer:

– Overvoltage detection

– EEPROM self-test at power-on

– Continuous ROM parity check

– Continuous state machine self-test

– Adder overflow

Failure Indication for HAR 24xy

Each die indicates a fault immediately by switching the

output signal to the selected error band in case that

the diagnostic mode is activated by the customer. The

customer can select if the output goes to the upper or

lower error band by setting bit number 7 in the

CUST_SETUP register (Table 3–3 on page 14). Fur-

ther details can be found in Section 4.13. on page 27.

The sensor switches the output to tristate if an over

temperature is detected by the thermal supervision.

The sensor switches the output to ground in case of a

VSUP wire break.

HAR2425 датащи(PDF) 16 Page - Micronas