ILD4071 Datasheet, PDF (11/25 Pages) Infineon Technologies AG – LED Driver for High Power LEDs

ILD4071
5.2
Power Supply Monitoring
Over- and Undervoltage shutdown
If the supply voltage V_REC drops below the Input under voltage threshold voltage V_REC,UVOFF, the power stage is
switched OFF and the device is in normal consumption mode (I_q,ON).
If V_REC rises again and reaches the Input under voltage startup threshold V_REC,UVON the power stage is restarted
and the device is back to normal operation mode.
Same behavior applies to overvoltage.
The internal status transistor is switching off during an overvoltage or undervoltage event on V_REC.
A detailed description of the under- and overvoltage behavior is displayed in Figure 3 below.
V_REC
V_{R EC,UVo ff}
V_{R EC,U Vh yst}
V_{R EC,OVoff}
V_{REC,U Von}
V_{R EC,OVh yst}
VR EC,OVo n
t
V_SW
t
I_LED
I_set
t
ST
ST pull-
down ON
ST pull-down transistor OFF
ST pull-
down ON
Figure 3 Over- and Undervoltage Protection
ST pull-down transistor OFF
t
ST pull-
down ON
Datasheet
11
Rev. 1.0, 2011-11-16