Power

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1 DC Supply

The AXIOM Beta developer kits ship with 5V DC power supply.

AXIOM Beta takes two 5V inputs (1x Microzed, 1x rest of electronics) and together draws 4A max, power consumption depends on operation and is in the 10-20 W range typically.




2 DC/DC Converter

Two 5V 2.5A output converters should be suitable.

For batteries both isolated as well as non-isolated DC converters are suitable.

https://octopart.com/search?q=171050601 would be an option.




3 Active Battery Mount

Axiom-beta-concept-enlosure-02 - above.png

Battery mount for NP-F970/F750/F550 batteries to power the AXIOM Beta. Includes power usage and capacity monitoring to estimate remaining charge and time remaining.


InfoLithium Protocol

Proprietary protocol from Sony that exchanges metadata between batteries and devices. Expected data inside the protocol includes: charge cycles, battery ID, remaining total capacity, remaining current capacity, etc. Only official Sony batteries incorporate this protocol, cheap replacement parts don't and some Pro Sony cameras refuse operation with batteries without InfoLithium communication.

Decrypting this protocol could give us more insight into the battery but is not essential as we can measure the discharge curve and estimate remaining capacity rather accurately that way.


Hacking References




4 Batteries

With batteries the conveniences are being able to:

  • measure power consumption (AXIOM Beta does that already)
  • estimate time left for operation (AXIOM Beta measures voltages - it still requires an algorithmn that turns the discharge curve into a time estimate)
  • set low voltage warning level

An external battery needs to provide two clean and accurate 5V supplies rated at 2 Amps or more. We have witnessed a battery that could not provide the required peak currents and resulted in visible horizontal "wave" noise artifacts being visible in the image of the Beta.

For connecting the Beta to dual USB power supplies a special cable is required:

Dual-USB-Power-cable-01.jpg

Components List:

1x  Molex   87439-0500              Pico Spox 5pin Housing
4x  Molex   87421-0000              Pico Spox Crimp Terminal AWG24
4x  19x36AWG - 45x40AWG             24AWG Flexible Cable
2x  CNC Tech 1002-024-01300         CONN USB A TYPE SOLDER ASSY
2x  CNC-Tech 1001-027-BL-01000      CONN HOOD USB A MALE BLACK
    CNC-Tech 1001-026-BE-01000      CONN HOOD USB A MALE BEIGE

TODO: add picture of assembled dual USB cable here.

We have successfully tested the following USB battery packs with the Beta so far:

https://www.amazon.de/Anker-PowerCore-20100mAh-Externer-Akku/dp/B00VJT3IUA/

When evaluating a new battery/power supply we recommend using two USB power meters between camera and battery: https://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Delectronics&field-keywords=usb+current+meter




Sony NPF970 1308575013000 352125.jpg

4.1 Sony NP-F*00

  • Dimensions: 70 x 38.5 x Depth mm (depth varies with capacity).
  • Voltage: 7.2 - 7.4V
  • Capacity: 2600mAh (~20Wh) - 6600mAh (~48Wh)

3D Model: https://cad.onshape.com/documents/378fdc7cb1bbff982219eee3/w/09323a194f01c81168e0369a/e/45714b1530f14e92fe5f37b5




On Labs: Battery System