AS3649

Datasheet - Detailed Descr i p ti on

www.ams.com/AS3649

1.0-2

16 - 39

A mobile phone camera flash system can trigger a diagnostic flash and a main-flash:

The diagnostic flash is initiated by the processor. After this diagnostic flash, the determined maximum flash current can be read back through the

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constant and additionally the camera system can use this current for picture quality adjustments - the waveforms for this concept are shown in

Figure 20:

Figure 20. Low Voltage Current Reduction Waveform with Diagnostic-Flash and Main-Flash Phase

Short Diagnostic Pulse.

If the diagnostic flash should be short (e.g. 4ms) it is recommended to operate this diagnostic flash at a different vcompl_adj (see page 27) and

higher vin_low_v (see page 24) settings compared to the main flash as shown in Figure 21:

Figure 21. Low Voltage Current Reduction Waveform with Short Diagnostic-Flash and Main-Flash Phase







 



 

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