SPI Driver for Enhanced Relay Control

TLE7238SL

Diagnostic Features

Data Sheet

23

Rev. 1.0, 2010-02-18

8

Diagnostic Features

The SPI of TLE7238SL provides diagnosis information about the device and about the load. The diagnosis

information of the protective functions of channel n is latched in the diagnosis flags Dn. It is cleared by the SPI

command CMD.CPL = 1. The CPL command clears itself with the next valid SPI communication frame.

The open load diagnosis of channel n is latched in the diagnosis flag OLn. This flag is cleared by reading the

according diagnosis register.

Following table shows possible failure modes and the according protective and diagnostic action.

Failure Mode

Comment

Open Load

Diagnosis, when channel n is switched on: none

Diagnosis, when channel n is switched off: according to voltage level at the

output pin, flag OLn is set after time

t

A diagnosis current can be enabled by SPI command DCCR.DCENn = 1.

Over Temperature

When over temperature occurs, the according diagnosis flag Dn is set. If the

affected channel n was active it is switched off.

The diagnosis flags are latched until they have been cleared by SPI

command CMD.CPL = 1.

Over Load

(Short Circuit)

When over load is detected at channel n, the affected channel is switched

off after time

t

The diagnosis flags are latched until they have been cleared by SPI

command CMD.CPL = 1.