The final noteworthy item on the iPod's PCB actually turns out to be the unit's CPU. The chip is a PP5002B-C chip made by PortalPlayer. Although the specifications of the version of the chip used in the iPod are not available on PortyalPlayer's website, specifications on their P5001 controller are available. Bearing the similar product names, we can speculate that not much has changed in the Apple specific chip. If this is in fact the case, then the PP5002B chip has a ARM7 TDMI based core with a coprocessor dedicated to real time encoding acceleration. The processor is able to not only decode MP3 and wma files (note that the iPod's chip can decode MP3 files up to 320 Kbps, MP3 variable bit rate, WAV, and AIFF files), it is also able to encode on the fly (a feature which Apple did not take advantage of in the iPod). The chip also features an integrated 32KB of SRAM and 8KB of cache. We are unsure of the operating frequency of the chip or how many MIPS the chip can handle, but the iPod never functioned slowly suggesting that there is plenty of power.
