elco_laden_220uH
External shutter DC/DC convertor module.
The VS14s Uniblitz shutter need 65V nominal as working voltage. I have build a DC/DC convertor to boost the voltage from the 7.2v battery to 67V on a 820 uF/330V Flash-elco. An ATtiny26 AVR controller is used to control the DC/DC module.
The tests with different inductors results into a working version where the primair load from 20V to 67V goes into 575ms. This time is only for the first powerup faze. Once on the 67V working voltage the convertor has only shortly to wakeup the voltage due to the small own internal discharge current. To see how the voltage change due to the shutter activation see:
www.flickr.com/photos/fotoopa_hs/8153417312/
The external VS14s shutter need a 4 msec puls to full open in 3.5msec. The 67V elco is used as powersystem to drive the high current during this short time. On this scoop picture, you see the elco discharge during this 4ms. The DC/DC convertor has to compensate as quick as possible to be ready for the next shutter sequence. The DC/DC convertor load the elco in 228 msec. The camera is set to 3 pictures/sec in repeat mode. the DC / DC converter is fast enough to keep up the 67V between the shots.
The hardware in test is show here:
www.flickr.com/photos/fotoopa_hs/7438491438/
www.flickr.com/photos/fotoopa_hs/7439316792/
www.flickr.com/photos/fotoopa_hs/7439422398/
www.flickr.com/photos/fotoopa_hs/7441575942/
elco_laden_220uH
External shutter DC/DC convertor module.
The VS14s Uniblitz shutter need 65V nominal as working voltage. I have build a DC/DC convertor to boost the voltage from the 7.2v battery to 67V on a 820 uF/330V Flash-elco. An ATtiny26 AVR controller is used to control the DC/DC module.
The tests with different inductors results into a working version where the primair load from 20V to 67V goes into 575ms. This time is only for the first powerup faze. Once on the 67V working voltage the convertor has only shortly to wakeup the voltage due to the small own internal discharge current. To see how the voltage change due to the shutter activation see:
www.flickr.com/photos/fotoopa_hs/8153417312/
The external VS14s shutter need a 4 msec puls to full open in 3.5msec. The 67V elco is used as powersystem to drive the high current during this short time. On this scoop picture, you see the elco discharge during this 4ms. The DC/DC convertor has to compensate as quick as possible to be ready for the next shutter sequence. The DC/DC convertor load the elco in 228 msec. The camera is set to 3 pictures/sec in repeat mode. the DC / DC converter is fast enough to keep up the 67V between the shots.
The hardware in test is show here:
www.flickr.com/photos/fotoopa_hs/7438491438/
www.flickr.com/photos/fotoopa_hs/7439316792/
www.flickr.com/photos/fotoopa_hs/7439422398/
www.flickr.com/photos/fotoopa_hs/7441575942/