4.1.1

Diode (DGND) in the ground line

A resistor (typ. RGND = 4.7 kΩ) should be inserted in parallel to DGND if the device drives an inductive load.

This small signal diode can be safely shared amongst several different HSDs. Also in this case, the presence

of the ground network produces a shift (≈600 mV) in the input threshold and in the status output values if the

microprocessor ground is not common to the device ground. This shift does not vary if more than one HSD shares

the same diode/resistor network.

4.2

Immunity against transient electrical disturbances

The immunity of the device against transient electrical emissions, conducted along the supply lines and injected

into the VCC pin, is tested in accordance with ISO7637-2:2011 (E) and ISO 16750-2:2010.

The related function performance status classification is shown in Table 12. ISO 7637-2 - electrical transient

conduction along supply line.

Test pulses are applied directly to DUT (device under test) both in ON and OFF-state and in accordance to ISO

7637-2:2011(E), chapter 4.

The DUT is intended as the current device only, with external components as shown in Figure 14. M0-9

application schematic.

Status II is defined in ISO 7637-1 Function Performance Status Classification (FPSC) as follows: “The function

does not perform as designed during the test but returns automatically to normal operation after the test”.

Table 12. ISO 7637-2 - electrical transient conduction along supply line

Test Pulse

2011(E)

Test pulse severity level

with Status II functional

performance status

Minimum number

of pulses or test

time

Burst cycle / pulse

repetition time

Pulse duration and

pulse generator internal

impedance

Level

US (1)

min

max

1

III

-112 V

500 pulses

0.5 s

2 ms, 10 Ω

2a

III

+55 V

500 pulses

0.2 s

5 s

50 µs, 2 Ω

3a

IV

-220 V

1h

90 ms

100 ms

0.1 µs, 50 Ω

3b

IV

+150 V

1h

90 ms

100 ms

0.1 µs, 50 Ω

4 (2)

IV

-7 V

1 pulse

100 ms, 0.01 Ω

Load dump according to ISO 16750-2:2010

Test B (3)

35 V

5 pulse

1 min

400 ms, 2 Ω

1. US is the peak amplitude as defined for each test pulse in ISO 7637-2:2011(E), chapter 5.6.

2. Test pulse from ISO 7637-2:2004(E).

3. With 35 V external suppressor referred to ground (-40°C < Tj < 150 °C).

VND9012AJ

Immunity against transient electrical disturbances

DS12727 - Rev 3

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