TLD1125EL Datasheet, PDF (26/36 Pages) Infineon Technologies AG – 1 Channel High Side Current Source Basic LED Driver

TLD1125EL
Load Diagnosis
10.2
Short Circuit to GND detection
The TLD1125EL has an integrated SC to GND detection. If the output stage is turned on and the voltage at the
output falls below V_OUT(SC) the potential on the IN_SET pin is increased up to V_{IN_SET(OL/SC)} after t_SC if the ST pin is
connected to GND. If the ST is open or connected to GND via a high ohmic resistor the fault is indicated on the
ST pin according to Chapter 8 after t_D. More details are shown in Figure 24. This condition is not latched. For
detecting a normal condition after a short circuit detection an output current according to I_OUT(SC) is driven by the
channel.
The filter time t_D is defined by the charging current I_D Pos. 10.3.10. The time is adjustable by the capacitor
connected to the D pin according the following equation:
t_{D, typ}
=
C_-----D----⋅_---V_{----D----(-t--h--)}
I_D
(11)
V _{IN _SET}
V_{IN _SET( OL )}
V_{IN _SET( ref )}
V_D
t
VD (th )
t_D
t_{IN _ SET(re se t)}
t
V_{OU T}
V_S
V_F
VOUT ( SC)
t
short circuit
occurs
short circuit
disappears
Figure 23 IN_SET behavior during short circuit to GND condition with ST connected to GND
Data Sheet
26
Rev. 1.0, 2013-08-08