STCF03 Datasheet, PDF (24/35 Pages) STMicroelectronics – High power white LED driver with I2C™ interface

Description of internal registers
STCF03
8.15
VOUTOK_N
This bit is set by the STCF03. It is used to protect the device, if the output is shorted. The
VOUTOK_N bit is set to HIGH at the start-up. Then a current generator of 20mA charges the
output capacitor for 360 µs typ. and it detects when the output capacitor reaches 100 mV. If
this threshold is reached the bit is set to LOW. If the output is shorted to ground or the LED
is shorted this threshold is never reached: the bit stays HIGH, ATN pin is pulled down and
the device will not start. This bit is reset following a read operation of the STAT_REG.
Figure 13. VOUTOK_N behavior
Table 16. Status register details
Bit Name
F_RUN
LED_F
NTC_W
(STAT_REG) (STAT_REG) (STAT_REG)
NTC_H
(STAT_REG)
OT_F
VOUTOK_N
(STAT_REG) (STAT_REG)
Default value
0
0
0
0
0
0
Latched ⁽¹⁾
NO
YES
YES
YES
YES
YES
Forces
NO
YES
NO
Ready mode
when set
YES
YES
YES
Sets ATN
NO
LOW when
set
YES
YES
YES
YES
YES
1. YES means that the bit is set by internal signals and is reset to default by an I²C read operation of STAT_REG NO means
that the bit is set and reset by internal signals in real-time.
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