VNQ830M datasheet(10/20 Pages) STMICROELECTRONICS

10 / 20 page

10/20

VNQ830M

Solution 2: A diode (DGND) in the ground line.

A resistor (RGND=1kΩ) should be inserted in parallel to

DGND if the device will be driving an inductive load.

This small signal diode can be safely shared amongst

several different HSD. Also in this case, the presence of

the ground network will produce a shift (

j600mV) in the

input threshold and the status output values if the

microprocessor ground is not common with the device

ground. This shift will not vary if more than one HSD

shares the same diode/resistor network.

LOAD DUMP PROTECTION

Dld is necessary (Voltage Transient Suppressor) if the

load dump peak voltage exceeds VCC max DC rating. The

same applies if the device will be subject to transients on

the VCC line that are greater than the ones shown in the

ISO T/R 7637/1 table.

µC I/Os PROTECTION:

If a ground protection network is used and negative

transients are present on the VCC line, the control pins will

be pulled negative. ST suggests to insert a resistor (Rprot)

in line to prevent the

µC I/Os pins to latch-up.

The value of these resistors is a compromise between the

leakage current of

µC and the current required by the

HSD I/Os (Input levels compatibility) with the latch-up limit

µC I/Os.

-VCCpeak/Ilatchup ≤ Rprot ≤ (VOHµC-VIH-VGND) / IIHmax

Calculation example:

For VCCpeak= - 100V and Ilatchup ≥ 20mA; VOHµC ≥ 4.5V

Ω ≤ R

prot ≤ 65kΩ.

Recommended Rprot value is 10kΩ.

VNQ830M Datasheet(PDF) 10 Page - STMicroelectronics