PLATFORM SYSTEM-ON-CHIP DESIGN
Prof. Don Bouldin, University of Tennessee
System-on-Chip (SoC) design may involve the mixing on a single IC
a microprocessor core (e.g. ARM, MIPS), PCI bus interface, analog
components and numerous digital processing functions. Designers
are increasingly reusing significant portions of previous
designs to reduce the time to market which generally results in
greater revenue for the product. Reuse of previous designs has
been occurring for decades. Initially, only simple library cells
were implemented with reuse in mind and this continues today. In
the past few years, major functions have been implemented as
virtual components. Since these may have been developed by
designers in other companies, their reuse involves a combination
of effort and risk in a new design. To minimize these, some
organizations are internally standardizing on a set of virtual
components and any associated software to develop their own SoC
platform. Using platform-based design allows the organization to
develop a complete SoC that is central to its product line. Once
the SoC plaform is fully operational, derivative designs in which
only a few virtual components are added or dropped can be
accomplished rapidly. Developing a complete SoC with ten or more
virtual components by a fixed deadline is no easy task.
Designers may encounter business and legal problems in obtaining
the virtual components and may find that information is missing.
Developing a platform permits designers to overcome all of these
uncertainties without risking the delay of a product. The
platform SoC also provides software developers with working
silicon they can use. The organization can market the platform
SoC to customers as a demonstration of what can be done and even
provide the customers with the opportunity to commence their own
product development using the existing SoC. Whenever the
customer determines that it is worthwhile to have a derivative
design customized for his product needs, the platform SoC
designers add or subtract a small number of virtual components
and revise the associated software. The derivative design can
likely be done in less than six months from concept to
production.
Several organizations are using this platform-based design
approach. Philips Semiconductors has developed a divital video
platform SoC intended for set-top boxes. The SoC includes a 32-
bit MIPS microprocessor core plus Philips' own Trimedia core and
an MPEG-2 decoder. Interface circuitry for PCI, UART and USB are
also included. For additional information, access:
NASA Paper
NEXPERIA
Tality, the design services spin-off of Cadence, has developed
two SoC platforms. One includes both an ARM microprocessor core
coupled with the popular OAK digital signal processor. Another
platform is targeted for the bluetooth wireless market. For
additional information, access:
ARM-OAK
BLUETOOTH
Infineon has developed a triple-mode SoC platform for wireless
applications. It includes a 32-bit microcontroller and a digital
signal processor. For additional information, access:
INFINEON
FPGA vendors have integrated CPU cores onto their chips and now
offer platform SoCs that are programmable. Triscend offers both
the 8032 8-bit microcontroller and the 32- bit ARM7TDMI core
with its programmable logic family. For additional
information, access:
TRISCEND
Xilinx offers a choice of the IBM PowerPC, Intel's StrongARM and
Pentium class, and QED processors for its Virtex and Spartan
product line. The PowerPC 405 is embedded as a hard-core in the
Virtex-II architecture and can operate at 300 MHz to produce 420
Dhrystone MIPs. For additional information, access:
XILINX
Atmel offers the popular 8051, ARM and AVR 8-bit microcontrollers
embedded in its programmable product line. A field-
programmable system-level integrated circuit starter kit is
available at very low cost. For additional information, access:
ATMEL
Altera offers a choice of CPU cores including the ARM, MIPS
Technologies and Altera's internally developed Nios embedded
processor. For additional information, access:
ALTERA
Gigascale Platform-Based Design Overview (pdf)
MICROELECTRONIC SYSTEMS NEWS
dbouldin@tennessee.edu