PORTLAND, Ore.—Freescale Semiconductor Inc. appeared to one-up Texas Instruments Inc. Wednesday (Nov. 17) by rolling out a digital signal processor (DSP) core that achieved a higher rating from benchmarking consulting firm BDTI Inc.
Last week, TI reported that its C66x DSP core achieved a BDTImark2000 score of 16,690.Freescale countered Wednesday that its new redesigned SC3850 core achieves a BDTIsimMark2000 score of 18,500. Since Freescale's redesigned SC3850 core is not yet sampling, the benchmarking has a slightly different nomenclature than the one applied to TI's core, according to Freescale.
As network operators convert from 3G to 4G, the system-on-chip (SoC) DSPs that execute the increasingly complex air-interface protocols—from LTE to WiMAX to WCDMA and HSPA+—are waging a benchmark war.
Used in its new MSC8157/8 basestation processors, Freescale claims to have offloaded the most complex 4G tasks—such as managing multiple-input-multiple-output (MIMO) antennas—into a dedicated accelerator called Maple, instead of adding general-purpose floating-point units like TI.
"What is most interesting about Maple is that the floating-point operations it performs are application specific," said Scott Aylor, director of DSP products at Freescale’s networking and multimedia group. "By making it a dedicated accelerator, it has very low latency when processing signals from the most common antenna configurations, compared to using a general-purpose floating-point core."
Today's base stations often have to resort to a specialized FPGA to offload achieve low latency in data steaming tasks like MIMO, according to Freescale (Austin, Texas), but now its Maple dedicated accelerator can handle those complex two-, four- or eight-parallel antenna configurations with its Maple accelerator alone, obviating the need for an FPFA in basestations using its new MSC8157/8 processors.
Freescale's new basestation DSP aims to ease transition from 3G to 4G with application-specific hardware units.
"Freescale's Maple-accelerator is fantastic--that's the secret sause which makes Freescale's DSP more desirable by some companies over TI's approach," said Will Strauss, principal analyst at Forward Concepts Co. (Tempe, Ariz.). "TI is still number one—with more than 50 percent market share compared to Freescale which has 25-to-30 percent—but some companies feel that Maple is a more elegant way of achieving the same functionality."
Frescale's new MSC8157/8 basestation DSPs utilize its 45-nanometer CMOS process, providing six-cores per chip and software compatibility with its previous generation MSC8156 DSPs. Firmware is provided to ease the development of multimode basestations that can handle 3G-LTE, WCDMA-HSPA+, WiMAX and 4G-LTE-Advanced.