TLE7243SL Datasheet, PDF (16/28 Pages) Infineon Technologies AG – 8 Channel Protected Low-Side Relay Switch

SPI Driver for Enhanced Relay Control
SPIDER - TLE7243SL
Protection Functions
6
Protection Functions
The device provides embedded protective functions. Integrated protection functions are designed to prevent IC
destruction under fault conditions described in this datasheet. Fault conditions are considered as “outside” normal
operating range. Protection functions are not designed for continuous repetitive operation.
6.1
Over Load Protection
The SPIDER - TLE7243SL is protected in case of over load or short circuit of the load. After time t_OFF(OVL), the over
loaded channel n switches off and the according diagnosis flag Dn is set.The channel can be switched on after
clearing the diagnosis flag. Please refer to Figure 7 for details.
IN1
t_{OFF( OVL )}
Program OUT 1 to
t
I_OUT1
STANDBY and to
I_{OU T( OVL )}
IN1 again
IN1 = 01_b
D1 = 0_b
D1 = 1_b D1 = 0_b
t
OverLoad.emf
Figure 7 Shut down at over load
The current sink to ground ensures that the channels switch off in case of open input pin. The zener diode protects
the input circuit against ESD pulses. After power-on reset, the device enters idle mode.
6.2
Over Temperature Protection
A temperature sensor for each channel causes an overheated channel n to switch off to prevent destruction and
the according diagnosis flag Dn is set. The channel can be switched on after clearing the diagnosis flag. Please
refer to Chapter 7.1 for information on diagnosis features.
6.3
Reverse Polarity Protection
In case of reverse polarity, the intrinsic body diode of the power transistor causes power dissipation. The reverse
current through the intrinsic body diode of the power transistor has to be limited by the connected load. The V_DD
and V_DDA supply pins must be protected against reverse polarity externally. The over temperature and over load
protection is not active during reverse polarity.
Datasheet
16
Rev. 1.0, 2009-09-30