Q67006-A9315 Datasheet, PDF (11/17 Pages) Infineon Technologies AG – Smart Quad Low-Side Switch

Data Sheet TLE 6220 GP
Diagnostics
FAULT - Fault pin. There is a general fault pin (open drain) which shows a high to low transi-
tion as soon as an error occurs for any one of the four channels. This fault indication can be
used to generate a µC interrupt. Therefore a ‘diagnosis’ interrupt routine need only be called
after this fault indication. This saves processor time compared to a cyclic reading of the SO
information.
As soon as a fault occurs, the fault information is latched into the diagnosis register. A new
error will over-write the old error report. Serial data out pin (SO) is in a high impedance state
when CS is high. If CS receives a LOW signal, all diagnosis bits can be shifted out serially.
The rising edge of CS will reset all error registers.
Full Diagnosis
For full diagnosis there are two diagnostic bits per channel configured as shown in Figure 1.
Diagnostic Serial OUT (SO)
7 6 5 4 32 1 0
Ch.4 Ch.3 Ch.2 Ch.1
HH
Normal function
HL
Overload, Shorted Load or Overtemperature
LH
Open Load
LL
Shorted to Ground
Figure 1: Two bits per channel diagnostic feedback
Normal function: The bit combination HH indicates that there is no fault condition, i.e. normal
function.
Overload, Short Circuit to Battery (SCB) or Overtemperature: HL is set when the current
limitation gets active, i.e. there is a overload, short to supply or overtemperature condition.
Open load: An open load condition is detected when the drain voltage decreases below 3 V
(typ.). LH bit combination is set.
Short Circuit to GND: If a drain to ground short circuit exists and the drain to ground current
exceeds 100 µA, short to ground is detected and the LL bit combination is set.
A definite distinction between open load and short to ground is guaranteed by design.
The standard way of obtaining diagnostic information is as follows:
Clock in serial information into SI pin and wait approximately 150 µs to allow the outputs to
settle. Clock in the identical serial information once again - during this process the data com-
ing out at SO contains the bit combinations representing the diagnosis conditions as described
in Figure 1.
V1.1
Page 11
26.Aug. 2002