TLD1311EL_15 Datasheet, PDF (24/33 Pages) Infineon Technologies AG – 3 Channel High Side Current Source

V_EN
VEN(on )
V_{EN(off )}
V_{IN _SET}
VIN_SET (ref )
VST
V_{ST (N- 1)}
VN-1
VN- 1(th )
TLD1311EL
Load Diagnosis
t
t
Slope depends on
impedance at ST-pin
t
tN -1
t
V_OUT
VS
VS – VPS( N-1 )
V_F
t_{ON (EN)}
open load open load
occurs disappears
t
Figure 19 IN_SET and ST behavior during open load condition (ST unconnected)
The N-1 status is latched. The output stages can be re-enabled by a Low to High transition at the EN pin or by a
Power on reset. To provide a Limp Home functionality (lower number of LEDs instead of complete deactivation)
in the case of a partially damaged LED array, the N-1 filter time t_N-1 can be used. If a PWM signal with an ON-time
of less than t_N-1 is applied to the VS and EN pins, the N-1 detection feature will not be activated.
If there is more than one device used for N-1 detection the maximum number of devices, which can be connected
as shown in Figure 21, is limited to n_N-1. The maximum number of devices in N-1 configuration is calculated
Data Sheet
24
Rev. 1.1, 2015-03-19