stcf05tbr STMicroelectronics, stcf05tbr Datasheet - Page 24

• Manufacturer Part Number: stcf05tbr
• Description: High Power White Led Driver With I?c Interface
• Manufacturer: STMicroelectronics

Registers description
9.13
9.14
9.15
9.16
9.17
9.18
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LED_O
This bit is set by the STCF05 when the voltage seen on the VOUT pin is V
during a torch or flash operation. This condition can be caused by an open LED, indicating a
LED failure. The device automatically goes into ready mode to avoid damage. Internal high
frequency filtering avoids false detections. This bit is reset by the STCF05 following a read
operation of the STAT_REG.
NTC_W
This bit is set HIGH by the STCF05 and the ATN pin is pulled down, when the voltage seen
on the pin R
value at the LED measured by the NTC. The device is still operating, but a warning is sent to
the microprocessor. This bit is reset by the STCF05 following a read operation of the
STAT_REG.
NTC_H
This bit is set HIGH by the STCF05 and the ATN pin is pulled down, when the voltage seen
on the pin R
value at the LED measured by the NTC. The device is put in ready mode to avoid damaging
the LED. This bit is reset by the STCF05 following a read operation of the STAT_REG.
OT_F
This bit is set HIGH by the STCF05 and the ATN pin is pulled down, when the chip over-
temperature protection (~140 °C) has put the device in ready mode. This bit is reset by the
STCF05 following a read operation of the STAT_REG.
OC_F
This bit is set high by the STCF05 when the max peak inductor current threshold is reached
(3 A programmable #). The OC_F bit is not latched into the STATUS reg. and the ATN pin
remains HIGH.
VOUTOK_N
This bit is set by the STCF05. 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 20 mA 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.
X
X
exceeds V
exceeds V
REF4
REF5
. This threshold (1.2 V) corresponds to an excess temperature
= 0.56 V. This threshold corresponds to a warning temperature
Doc ID 15257 Rev 4
REF2
> 11.6 V
STCF05