I need my camera (Canon EOS 7D Mark II) powered in terrain for a long period of time (10 + hours, mostly idling.)
I bought a dummy battery with a 5V to 8V boost converter (camera uses a 7.2 Li-ion battery,) which "almost works". I can turn on the camera, switch on live-view, record video, but I can't take pictures.
I suspect the DC-DC converter cannot handle the current spike needed (it should be up to 3 A) for taking pictures. I did not crack open it for now, so I have no idea what it consists of.
Prior power source should not be problem, as I tried a powerful powerbank and also a mains adapter. But that is not the issue now.
I decided to switch the provided DC-DC converter with a more powerful one. I bought a DC-DC boost converter based on the XL6009E1 IC (image and schematic below.) Note that I am not certain with 0.1 microF capacitor values, but other should fit. It should handle input current of 4 A according to product description (it would burn without heat sink/cooling I guess, but I only need short spikes of high current.)
After hooking up 5V to the input of the boost converter, setting 8 V on output, and delivering it to the camera through the dummy battery - nothing happens. The camera won't even turn on. I measured 8.00 V while connected. There is also small current: 0.01 - 0.02 A.
The measured current could be no-load current (18 mA according product description.
The polarity was correct. I suspected boost converter to be defective, so I hooked up a small DC motor on the output. It ran, measuring almost 1A of current.
- Why is the boost converter not delivering enough current to the camera?
- Am I doing something wrong?
- What should be changed?
I do not believe that there is more than 1 A of current needed for turning on the camera. The smaller (and assuming also weaker) original boost module was capable of it.
I measured the current flowing to the camera when switching on with the original boost converter that came with the dummy battery. It slowly rises to 0.7 A @ 8V. It was measured only with a multimeter several times, this was the peak. Also, I tried to take a picture and it spiked to 1.5 A @ 8V then an error message appeared on the camera.
While this error message is really most probably caused by an insufficient prior power source, it does not explain why the camera is not even turning on with the XL6009 boost converter. It can successfully output 1.5 A @ 8V (tested on a bigger DC motor.)