TLD5098EL_15 Datasheet, PDF (21/41 Pages) Infineon Technologies AG – Multitopology LITIX Power DC/DC Controller IC

Infineon® LITIX™ Power
TLD5098EL
Protection and Diagnostic Functions
9
Protection and Diagnostic Functions
9.1
Description
The TLD5098EL has integrated circuits to diagnose and protect against output overvoltage, open load, open
feedback and overtemperature faults. Additionally the FBH and FBL potential is monitored and in case the
LED load short circuits to GND (see description Figure 9-7) the regulator stops the operation and protects the
system. In case any of the six fault conditions occur the PWMO and IVCC signal will change to an active logic
LOW signal to communicate that a fault has occurred (detailed overview in Figure 9-1 and Figure 9-2below).
Figure 9-3 illustrates the various open load and open feedback conditions. In case of an overtemperature
condition the integrated thermal shutdown function turns off the gate drivers and internal linear voltage
regulator. The typical junction shutdown temperature is 175°C (T_j,SD Parameter 9.2.2). After cooling down the
IC will automatically restart. Thermal shutdown is an integrated protection function designed to prevent IC
destruction and is not intended for continuous use in normal operation (Figure 9-5). To calculate the proper
overvoltage protection resistor values an example is given in Figure 9-6.
Input
Output
Overvoltage
Open Load
Short to GND
Open Feedback
Protection and
Diagnostic Circuit
OR
Output
SWO and PWMO
Gate Driver Off
Overtemperature
OR
Input
Undervoltage
Linear Regualtor
Off
Figure 9-1 Protection and Diagnostic Function Block Diagram
Data Sheet
21
Revision 1.2
2015-03-12