Journal of Signal Processing Systems

, Volume 62, Issue 3, pp 373–382 | Cite as

Parallel Architecture Core (PAC)—the First Multicore Application Processor SoC in Taiwan Part I: Hardware Architecture & Software Development Tools

  • David Chih-Wei Chang
  • Tay-Jyi LinEmail author
  • Chung-Ju Wu
  • Jenq-Kuen Lee
  • Yuan-Hua Chu
  • An-Yeu Wu


In order to develop a low-power and high-performance SoC platform for multimedia applications, the Parallel Architecture Core (PAC) project was initiated in Taiwan in 2003. A VLIW digital signal processor (PACDSP) has been developed from a proprietary instruction set with multimedia-rich instructions, a complexity-effective microarchitecture with an innovative distributed & ping-pong register organization and variable-length VLIW encoding, to a highly-configurable soft IP with several successful silicon implementations. A complete toolchain with an optimizing C compiler has also been developed for PACDSP. A dual-core PAC SoC has been designed and fabricated, which consists of a PACDSP core, an ARM9 core, scratchpad memories, and various on-chip peripherals, to demonstrate the outstanding performance and energy efficiency for multimedia processing such as the real-time H.264 codec. The first part of the two introductory papers of PAC describes the hardware architecture of the PACDSP core, its software development tools, and the PAC SoC with dynamic voltage and frequency scaling (DVFS).


Parallel Architecture Core PACDSP VLIW DSP VLIW compiler DVFS Heterogeneous multicore Application processor 


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • David Chih-Wei Chang
    • 1
  • Tay-Jyi Lin
    • 2
    Email author
  • Chung-Ju Wu
    • 3
  • Jenq-Kuen Lee
    • 3
  • Yuan-Hua Chu
    • 4
  • An-Yeu Wu
    • 5
  1. 1.MediaTek Inc.HsinchuTaiwan
  2. 2.National Chiao Tung UniversityHsinchuTaiwan
  3. 3.National Tsing Hua UniversityHsinchuTaiwan
  4. 4.Industrial Technology Research InstituteHsinchuTaiwan
  5. 5.National Taiwan UniversityTaipeiTaiwan

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