Description of internal registers

STCF03I

20/33

8

Description of internal registers

8.1

PWR_ON

When set, it activates all analog and power internal blocks including the NTC supporting

circuit, and the device is ready to operate (ready mode). As long as PWR_ON=0, only the

I²C interface is active, minimizing Stand-by Mode power consumption.

8.2

TRIG_EN

This bit is AND-ed with the TRIG pin to generate the internal signal FL_ON that activates

flash mode. By this way, both soft-triggering and hard-triggering of the flash are made

possible. If soft-triggering (through I²C) is chosen, the TRIG pin is not used and must be

kept HIGH (VI). If hard-triggering is chosen, then the TRIG pin has to be connected to a µP

I/O devoted to flash timing control, and the TRIG_EN bit must be set in advance. Both

triggering modes can benefit of the internal flash time counter, that uses the TRIG_EN bit

and can work either as a safety shut-down timer or as a flash duration timer. Flash mode

can start only if PWR_ON=1. LED current is controlled by the value set by the FDIM_0~3 of

the DIM_REG.

8.3

TCH_ON

When set from ready mode, the STCF03I enters torch mode. The LED current is controlled

by the value set by the TDIM_0~3 of the DIM_REG.

8.4

NTC_ON

When the NTC_ON bit is set to HIGH and the device is in ready mode, then the comparators

that monitor the LED temperature are activated. NTC-related blocks are always active

regardless of this bit in torch mode and flash mode.

Table 9.

I²C register mapping function

Register name

SUB ADDRESS (hex)

Operation

CMD_REG

00

R / W

DIM_REG

01

R / W

AUX_REG

02

R / W

STAT_REG

03

R only

Table 10.

Command register

CMD_REG

(write mode)

MSB

LSB

SUB ADD=00

PWR_ON

TRIG_EN

TCH_ON

NTC_ON

FTIM_3

FTIM_2

FTIM_1

FTIM_0

Power ON

RESET Value

0

0

000

0

0

0