Specifications for the Matsushita DVD-RAM UJ-840S

Techwalla may earn compensation through affiliate links in this story.

Long before the Japanese electronics company began using the Panasonic name in 2008, many of its products bore the Matsushita nameplate. One such product was the UJ-840S optical drive. Also branded as Matshita or Matshita Panasonic, this CD/DVD drive could be found on laptops from major computer manufacturers such as HP, Sony and Panasonic itself. Although Panasonic has stopped making the UJ-840S, it may still be available for purchase at a few online retail outlets.



The Matsushita UJ-840S had the "Super Multi" designation, which meant that in addition to playing prerecorded CDs and DVDs -- known as CD-ROM and DVD-ROM, respectively -- users could play and record the following optical disc formats: CD-R/RW, DVD-RAM, DVD-R/RW and DVD+R/RW. The UJ-840S was also compatible with dual-layer DVDs, which have two recordable dye layers for storing data, instead of one. Consequently, dual-layer DVDs can store twice as much data as single-layer ones.


Video of the Day


The Matsushita UJ-840S played and recorded -- or "read" and "wrote" -- DVDs at a slower speed than it did CDs. The optical drive could read CD-ROMs at 24x, while the reading speed for DVD-ROMs was 8x. In terms of writing performance, CD-Rs and CD-RWs had rates of 24x and 10x, respectively. Of the recordable DVD formats, the UJ-840S could record DVD+/-Rs the fastest, at a rate of 8x. DVD-RAMs and DVD+/-RWs were next in line, with rates of 5x and 4x, respectively. Because of their larger data storage capacity, dual-layer DVDs had the slowest writing speed, at 2.4x.



Manufacturers connected the Matsushita UJ-840S to their computers with its Integrated Drive Electronics connector. Retroactively known as Parallel AT Attachment, or Parallel ATA, the interface adhered to ATA Packet Interface standards. The UJ-840s had a 2-MB buffer, a small section within the drive for temporarily storing data for faster access.


Physical Characteristics

The Matsushita UJ-840S used a tray-loading mechanism for playing optical discs. The optical drive had an eject button that pulled out a motorized tray when pressed. The user could then place the disc on the tray. Weighing almost 0.5 lbs., the UJ-840S used the traditional 5.25-inch form factor. It had a length of 127 mm, height of 12.7 mm and width of 128 mm.