Detailed description

STCF03

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TRIG_EN bit, and also resets the F_RUN bit. The ATN pin is pulled down to inform the µP

that the STAT_REG has been updated.

9.5

External (µP) temporization using TRIG_EN bit

Even if it is possible, it is not recommended to use the TRIG_EN bit to start and stop the

Nevertheless, if this operation mode is chosen, the TRIG pin has to be kept High (logic level

the Time Counter will Time-out Flash operation and keep the LED dissipated energy

dissipated by the LED within safe limits in case of SW deadlock.

9.6

Single Flash using internal temporization

(soft-triggering). The first solution is recommended for an accurate start time, while the

STCF03 internal temporization and its accuracy is determined by the internal oscillator. For

hard-triggering it is necessary to set the TRIG_EN bit in advance. For soft-triggering the

a delay time between the moment the Flash is triggered and when it appears. This delay is

caused by the time necessary to charge up the output capacitor, which is around 1.2 ms

depending on battery voltage and output current value. Once triggered, the flash operation

will be stopped when the Time Counter reaches zero. As soon as the Flash is finished, the

F_RUN bit is reset, the ATN pin is pulled down for 11 µs to inform the µP that the STAT_REG

has been updated and the device goes back to Ready mode. If it is necessary to make a

Flash longer than the internal timer allows or a continuous Flash, then the FTIM must be

get a continuous FLASH, set FTIM to 1.5 s and every 1 s reload the CMD_REG.

9.7

Multiple Flash using internal temporization

This operation has to be processed as a sequence of single flashes using internal

temporization starting from hard or soft triggering. Since the TRIG_EN bit is reset at the end

of each flash, it is necessary to reload the CMD_REG to start the next one.