Gemini 4:4:4 User Manual
021313
www.Gemini444.com
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P a g e
Best Practices for Handling SSD Media, BNC Cables and Power
In order to avoid catastrophic data loss, and reap the best use of your Convergent Design SSD
cards, it is imperative you read this document thoroughly.
Background
The 256 and 512GB 1.8” SSDs (Solid-State Drives) utilized with the Gemini 444 recorder offer a
tremendous amount of reliable storage in a very small form factor. They are marvels of advanced
semiconductor processing, packing upwards of 600 Billion transistors in a package that fits in the
palm of your hand. These high density SSDs offer amazing data-rates, up to 500MB/sec read and
260MB/sec write speeds, enabling recording of uncompressed HD and raw video up to 4K
resolution.
But high data-rates require associated high-power, as the I/O throughput is achieved by reading /
writing to eight (or more) individual ICs (integrated circuits) in parallel. The highest power
requirement occurs during a write operation, where power consumption of 5 watts per 512GB SSD
is not uncommon. Power consumption is directly dependent on the write speed, the greater the
power. Additionally, high frame-rate (48/50/60 fps) video requires writing video to two SSD drives
in parallel, which can raise the overall SSD power to close to 10 Watts. Add the power
requirements for the LCD and other control circuit and total Gemini power can reach 16 watts.
SSD drives are very sensitive to power glitches, especially during write operations. A significant
drop in the voltage can cause an errant write in the SSD, which can corrupt a frame of video,
scramble the file directory/FAT or worse case cause an unrecoverable drive failure. Power
management is therefore crucial for reliable operation. Particularly challenging is managing the
power spike which occurs during the transition from idle mode to record as well as closing the files
at the conclusion of a record session. Power can instantly jump from 6 to 16 watts when the record
button is pressed. So a power system that seemed adequate in idle mode (live view) may instantly
cause the Gemini to reboot and wipe out one or more SSDs during the transition to record
mode. Inadequate power can also cause failures during file closing at the end of a record session,
which causes a second spike (due to updating FAT tables, etc).
Additionally, insufficient SSD power can also lead to failures during the offload of video data from
the SSD to a computer or loading new Gemini firmware updates onto the SSD. Anytime an SSD is
connected to a PC/MAC, the operating system may perform file indexing operations, which can
result in write operations to the SSD. Even in idle mode, SSDs perform housekeeping operations
DOWNLOAD: Service Bulletin, Best Practices
Handling SSD’s, BNC Cables & Power
