Data Sheet TLE 7230 R

V2.0

Page

2005-10-05

11

SPI Diagnostics:

As soon as a fault occurs for longer than the fault filtering time, the fault information is latched into the

diagnosis register (the Fault pin will also change from high to low state). A new error on the same chan-

nel will overwrite the old error report. Serial data out pin (SO) is in high impedance state when CS is

high. If CS receives a LOW signal, all diagnosis bits can be shifted out serially. If the sent command is

valid the rising edge of CS will reset all diagnosis registers and restart the fault filtering time. In case of

an invalid command the device will ignore the data bits and the diagnosis register will not be reset at the

rising CS edge.

Figure 1: Two bits per channel diagnostic feedback

Diagnostic Serial Data Out SO

HH

Normal function

HL

Overload , Shorted Load or Overtemperature

LH

Open Load (off)

LL

Short to GND

15

3

2

1

0

MSB

Ch.2

Ch.1

LSB

Ch.8

For Full Diagnosis there are two dedicated diagnostic bits per channel, as shown in Figure 1.

Normal function: The bit combination HH indicates that there is no fault condition, i.e. normal function.

Overload, Shorted Load or Overtemperature: HL is set if the current limitation becomes active, i.e.

in the event of an overload or short to supply event. Additionally, this bit combination is set in the event of

overtemperature of the corresponding channel.

Open load: LH is set if an open load is detected (in off state of the channel)

Short to GND: LL is set if a short to ground condition is detected (in off state)

Timing Figures

Figure 5: Power Outputs

t

t

80%

20%