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AS3635

Datasheet - D e t a i l e d D e s c r i p t i o n

8 Detailed Description

The AS3635 is a photoflash capacitor charger and an integrated IGBT driver for a Xenon flash. The capacitor charger

Additionally a charge pump is included to generate a stable 5V supply for accurate control of the IGBT on/off timings

independent of the battery supply.

output voltage resulting in an improved use of the available energy in the photoflash capacitor.

Note:

The AS3635 uses a WL-CSP (wafer level chip scale package) to optimize the PCB area required and minimize

the module size. Therefore the actual DIE is visible (and it is not molded in plastic as for other packages like

QFN or DFN) and the AS3635 is sensitive to external light. It has to be protected from direct light from the

Xenon tube.

Internal Circuit

Figure 15. Internal circuit

AS3635 Operation

The AS3635 allows charging and refresh cycles under complete software control. Two typical configurations are

shown in Figure 16 and Figure 17:

Figure 16 shows a configuration without any refresh between the pre-flash and the actual flash. Typically this is used

for applications where no noise at all should be generated on the battery when the camera is performing e.g. white

color balancing (between pre-flash and flash cycle).













 

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AS3635