Peregrine Semiconductor Corp of San Diego, CA, USA – a fabless provider of radio-frequency integrated circuits (RFICs) based on silicon-on-insulator (SOI) – has launched the UltraCMOS PE42723, an RF switch with what is claimed to be the highest linearity specifications on the market.
As an upgraded version of the PE42722, the new RF switch offers enhanced performance in a smaller package. Like its predecessor, the PE42723 exceeds the linearity requirements of the DOCSIS 3.1 cable industry standard and enables a dual upstream/downstream band architecture in cable customer premises equipment (CPE) devices.
The cable industry faces the challenge of supporting the consumer's increasing demand for more high-speed home data. The rapid adoption of video-streaming services is compounding the problem and putting enormous strain on the broadband ecosystem, from CPE devices to cable infrastructure, says Peregrine. As predicted in the Cisco Visual Networking Index (VNI), 5 million years of video content will cross the Internet each month in 2019. This estimate means nearly a million minutes of video will be streamed or downloaded every second. To keep up with consumer demand, in October 2013 the cable industry announced the DOCSIS 3.1 standard, offering multi-gigabit throughput. The standard set an ambitious goal for the industry, and one of the toughest challenges was to support the new linearity requirements and harmonics.
The PE42722 and PE42723 switches offer what is claimed to be a unique approach to solving the DOCSIS 3.1 linearity challenge when supporting a dual upstream/downstream band architecture. CPE devices (such as set-top boxes, cable modems and home gateways) had previously supported only one upstream/downstream band combination. The PE42722 and PE42723 are said to be the only RF switches that enable dual upstream/downstream bands to reside in the same CPE device. By using this dual-band architecture, CPEs can comply with the DOCSIS 3.1 cable industry standard, and multi-service operators (MSOs) have the flexibility to offer their customers new and expanded services. MSOs also benefit from the switches supporting both DOCSIS 3.0 and 3.1 requirements, allowing for a simple and cost-effective transition to DOCSIS 3.1.
"DOCSIS 3.1 represents a giant leap forward in achieving multi-gigabit data rates," comments Jim Koutras, director of product management at RF/analog and mixed-signal semiconductor firm MaxLinear of Carlsbad, CA, USA. "With their exceptional linearity, Peregrine's PE42722 and PE42723 RF switches simplify the transition from DOCSIS 3.0 to 3.1," he adds. "The ability to support dual upstream/downstream bands in the same CPE device is a critical enabler to making DOCSIS 3.1 a reality."
Before the introduction of the PE42722 in 2013, no switch had met the linearity requirements necessary to support a dual upstream/downstream band architecture, says Peregrine. To create this architecture, the switch is placed directly at the cable modem (CM) F-connector before the filters and must comply with the stringent DOCSIS 3.1 CM spurious emissions requirements of -50dBmV. Such a low spurious level requires the switch harmonic performance to be greater than -115dBc. The PE42722 and PE42723 are the only RF switches available that can achieve these high harmonic requirements, it is reckoned.
Covering a frequency range of 5-1794MHz, the PE42723 is a reflective SPDT RF switch that delivers high linearity and exceptional harmonic performance. At 17MHz, the second harmonic is -121dBc and the third harmonic is -140dBc. The switch's low insertion loss (0.3dB at 1218MHz) preserves noise figure and receiver sensitivity and achieves superior signal quality, along with providing high isolation of 54dB at 204MHz. The PE42723 features 3kV ESD protection on all pins.
Offered in a small 12-lead 3mm x 3mm QFN package, volume-production parts, samples and evaluation kits are available now. For 10,000-unit orders, each PE42723 switch costs $1.56.
