STCF04 Datasheet, PDF (16/43 Pages) STMicroelectronics – Cell phones and smartphones

Detailed description
8
Detailed description
STCF04
8.1
8.1.1
8.1.2
8.1.3
8.1.4
8.1.5
8.1.6
Logic pins
SCL, SDA pins
These are the standard CLOCK and DATA pins as defined in the I²C bus specifications.
External pull-ups are required according to I²C bus specifications.
FLASH pin
This input pin is internally AND-ed with the FLASH_ON bit to generate the internal signal
that activates the flash operation. This gives the user the possibility to accurately control the
flash duration using a dedicated pin, avoiding the I²C bus latencies (hard-triggering). Neither
internal pull-up nor pull-down is provided.
TORCH pin
This input pin is internally AND-ed with the TCH_ON bit to generate the internal signal that
activates the torch operation. Neither internal pull-up nor pull-down is provided.
RESET pin
This pin works as an external reset input. The microprocessor can use this pin to reset the
STCF04 at any time. Neither internal pull-up nor pull-down is provided. This pin is active
LOW.
ATN pin
This output pin (open drain, active LOW) is provided to better manage the information
transfer from the STCF04 to the microprocessor. Because of the limitations of a single
master I²C bus configuration, the microprocessor should regularly communicate with the
STCF04 to verify if certain operations have been completed, or to check diagnostic
information. Alternatively, the microprocessor can use the ATN pin to be advised that a new
data is available in the STAT_REG register, therefore avoiding continuous communication.
The information may then be read in the STAT_REG by a read operation via I²C which also
automatically resets the ATN pin to HIGH. The STAT_REG is also reset to 0. No internal
pull-up is provided.
ADD pin
This pin offers the opportunity of selecting one of the 4 possible I²C slave addresses.
Neither internal pull-up nor pull-down is provided. The pin must be connected to GND, VBAT,
SCL or SDA to select the desired I²C slave address (see Table 7). This pin cannot be left
floating.
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Doc ID 022927 Rev 3