VN920B5TR-E(2013) View Datasheet(PDF) - STMicroelectronics

Part Name

Description

Manufacturer

VN920B5TR-E
(Rev.:2013)

Single channel high-side solid state relay

STMicroelectronics 

Application information

3

Application information

Figure 19. Application schematic

+5V

Rprot

INPUT

VCC

μC

Rprot

CURRENT SENSE

RSENSE

GND

OUTPUT

VGND RGND

DGND

VN920B5-E

Dld

3.1

3.1.1

GND protection network against reverse battery

Solution 1: resistor in the ground line (RGND only)

This can be used with any type of load.

The following is an indication on how to dimension the RGND resistor.

1. RGND ≤ 600 mV / (IS(on)max)

2. RGND ≥ (-VCC) / (-IGND)

where -IGND is the DC reverse ground pin current and can be found in the absolute

maximum rating section of the device datasheet.

Power Dissipation in RGND (when VCC < 0: during reverse battery situations) is:

PD = (-VCC)2/ RGND

This resistor can be shared amongst several different HSDs. Please note that the value of

this resistor should be calculated with formula (1) where IS(on)max becomes the sum of the

maximum on-state currents of the different devices.

Please note that if the microprocessor ground is not shared by the device ground then the

RGND produces a shift (IS(on)max * RGND) in the input thresholds and the status output

values. This shift varies depending on how many devices are ON in the case of several high-

side drivers sharing the same RGND.

If the calculated power dissipation leads to a large resistor or several devices have to share

the same resistor then ST suggests to utilize Solution 2 (see below).

16/26

Doc ID 17608 Rev 2

Share Link: