At the cable TV industry consortium's CableLabs winter conference in Philadelphia today, Broadcom introduced a new 40nm Digital Transport Adapter (DTA) System on a Chip (SoC) for cable systems, the BCM7574. Brett Tischler, marketing director for Broadcom’s set-top box (STB) product line, says that the DTA frees up spectrum for cable operators to deliver more High-Definition (HD) and Video on Demand (VOD) services.
Cable operators must currently support ~45M analog TVs that are connected to cable systems in North America, says Tischler. A typical cable system has 860MHz-1GHz of bandwidth, and supporting analog channels can consume up 400MHz of that bandwidth. Operators could deliver four HD digital channels in the space of a single analog channel. By employing DTAs in their STBs, the digital-to-analog conversion takes place in the subscriber's home, freeing up cable capacity for Data Over Cable Service Interface Specification (DOCSIS 3.0) services.
The BCM7574 addresses the issue of slower channel switching times that consumers may experience when they switch from analog to digital STBs, with Broadcom’s FastRTV technology. The device also supports the new Federal Communications Commission (FCC) Commercial Advertisement Level Mitigation (CALM) requirements, to maintain consistent audio volume during commercials, program and channel changes. Tischler says that Broadcom is integrating new ultra-low power features into all of their STB SOCs, and the BCM7574
lowers system stand-by power to less than 100 milliwatts (mW), reducing average power consumption by up to 65% percent in a 24 hour period (assuming 8 hours of TV watching per day).
New hybrid gateway SoC
Broadcom is also introducing a new 40nm hybrid gateway System on a Chip (SoC) for set top boxes (STBs) at the CableLabs conference, to enable cable operators to securely deliver premium broadcast content converged with web-based content and services. The BCM7435 is a dual-core/quad-thread application processor, which can simultaneously transcode four digital media streams, with performance of 7000 Dhrystone Million Instructions Per Second (DMIPS).
Joe Del Rio, a marketing director for Broadcom’s set-top box line, says that the company's chip architects customized the BCM7435 based on MIPS processor cores. By getting down to the Register-Transfer Level (RTL), Broadcom's designers were able to extend security to the lowest level of cache and core processor operations, says Del Rio. The BCM7435 has the capacity to support multi-screen connected homes, with up to 22 concurrent video streams. The new security hardware in the device provides cable operators with the ability to support internet services, while ensuring that web apps do not introduce malware or circumvent content protection in premium pay-TV services. According to Del Rio, most cable operators will install Linux on STBs, but the BCM7435 can also run Android Ice Cream Sandwich. Broadcom showed such a STB reference design at the 2012 International Consumer Electronics Show, based on the previous generation MIPS-based BCM7425, enabled by Myriad's Alien Vue Android technology.
The BCM7435 has the same footprint as the BCM7425, with more than 200% higher applications CPU performance, according to Broadcom's press release. The hardware hypervisor in the BCM7435 supports multi-processor and multi-Operating System software platforms. Broadcom also says that the BCM7435 delivers a 300% increase in 3D graphics performance, and a 200% increase in Audio Processing compared to the previous generation BCM7425. Both devices provide Multimedia Over Coax (MoCA) 2.0 connectivity.