Power management is now and was then an important consideration. While far less complex than today's solutions, the PMP300 utilized a Maxim MAX1706 dc/dc converter as an efficient means to boost the 1.5-volt AA battery cell to the 3.3 V used for system power.
Packaging was less sophisticated than what's found in modern portable electronics, here requiring two boards to fit the entire surface-mount--but still peripheral-leaded--component set. Memory and control devices along with the LCD interface resided on one board while audio processing and power conversion filled a second of equal size, with a stacked board-to-board connector between the two.
Turning to a comparison with the Apple 2-Gbyte Nano, we still see standalone memory for media storage, moving from four separate chips totaling 32 Mbytes in the PMP300 to a single stacked four-chip memory package housing nearly two orders of magnitude more in flash storage capacity.
The dedicated digital audio processing and separate microcontroller of the PMP300 have migrated in today's Nano to a single media processor in the form of a Samsung chip. It combines system control and sophisticated sound and image processing on a common chip. As in the PMP300 however, the audio codec and associated headphone amplifier remain a separate device in the Apple product, likely reflecting a continued emphasis on output audio quality over maximum integration.
Power conversion in the Nano has escalated from the single switched supply of the PMP300 to a complex power management unit combined with two other power devices. Likewise, memory topology in the Nano has become more complex. While NAND is still used for song storage in both units, the Nano relies on additional NOR flash code memory and 32 Mbytes of buffer/scratch pad SDRAM.
In sum, the PMP300 seems to have set a generalized partitioning approach for today's flash-based player, and both designs rely on a mix of separate device functions over more-integrated but less-flexible alternatives. While media features, storage and other user-interface features have come a long way, one can see common design philosophies in both today's Nano and the market-launching PMP300 that is eight years its senior.
Despite (and because of) the advancing component set, the standalone MP3 player is still with us in modern forms popularized by Apple, among many others. Diamond and Rio may be distant memories, but the PMP300 got a ball rolling that continues to gather steam. In short, the Rio bootstrapped a music and media market that is still shifting, in both how content is played and how it is bought. n
In Brief
When Diamond Rio's PMP300 launched the MP3 player market back in 1998, it quickly became both a popular device and the original lightning rod for digital rights management. Along with setting legal precedents for content and defining a new product category, the PMP300 holds some design parallels to modern equivalents in the portable music player arena. The capabilities of today's popular devices have obviously leapfrogged those of the PMP300, but the design partitioning remains arguably more similar than different despite almost nine years of evolution.
David Carey is president of Portelligent (www.teardown.com). The Austin, Texas, company produces teardown reports and related industry research on wireless, mobile and personal electronics.
