Single Chip Houses Analog/Digital TV Receiver

March 17, 2006
Based on patented wideband active RF filtering technology, this single IC can receive all analog and digital television signals with fast channel tuning that settles in less than 10 ms.

Television technology will undergo a dramatic makeover in the next several years, as terrestrial, satellite, and cable broadcasters make the transition from analog to digital. Manufacturers of consumer televisions, however, have already gotten the jump on digital technology with sets bearing "digital-ready" or "high-definition (HD) ready" labels to entice consumers. Many of these newer liquid-crystal-display (LCD), plasma, or rear-projection televisions still incorporate traditional "can" type, metal-enclosed discrete-component tuners. But a growing number of television set designers are discovering the benefits of a single-chip tuner from XCEIVE Corp. (Santa Clara, CA), the model XC3028. The Orthoclase receiver integrated circuit (IC) includes all analog and digital circuitry needed to tune from 42 to 862 MHz and support all analog and digital television standards with blazing settling time of 10 ms.

The XC3028 (Fig. 1) is housed in a plastic, 48-pin QFN package, with no external tunable parts. The miniature, lead-free packaged IC measures just 7 × 7 × 0.85 mm, in sharp contrast to traditional "can" style television tuners (Fig. 2), typically constructed with discrete components and surrounded by a metal enclosure to ensure proper shielding and minimize crosstalk. The XC3028 requires no shielding, yet delivers impressive electrical performance, including a worst-case noise figure of 6 dB (typical 4dB) and typical video signal-to-noise ratio (SNR) of 55 dB, weighted (see table).

The XC3028 is truly a single-chip solution in that it does not require an external low-noise amplifier (LNA) to improve sensitivity, nor does it need external surface-acoustic-wave (SAW) filters to improve rejection of unwanted interference. It also includes a high performance video demodulator (Vif/Sif). The XC3028 delivers a gain-control range of 80 dB with its own LNAs, resulting in receive sensitivity of -83 dBm or better for ATSC signals. The onboard DSP provides dynamic control of levels and signal rejection according to monitored input signal levels and quality to provide the wide dynamic range needed particularly when working with over-the-air television broadcasts. This not only helps in receiving very weak signals but also prevents receiver front end overloads. Also in contrast to larger (some as large as 2 X 4 in.), more power-hungry can tuners, the XC3028 consumes a mere 1.2 W of power from 1.8- and 3.3-V supplies.

The XC3028 is a highly integrated chip that combines analog and digital circuitry, from an input filter and phase locked-loop (PLL) driven mixer surrounded by variable-gain amplifiers to a high-speed analog-to-digital converter (ADC), digital signal processor (DSP), and dual digital-to-analog converters (DACs). Its clean architecture (Fig. 3) supports all analog and digital television standards, allowing set designers to eliminate multiple chips or can tuners and simplify their tuner inventories. The XC3028 supports the NTSC, PAL, and SECAM analog standards and provides CVBS video and SIF/AF audio outputs. It also supports ATSC, DVB-C, DVBT, and ISDB-T digital standards by generating a digital demodulator interface signal that can then be processed by additional digital demodulation circuitry within a television set design.

The combination of functions and features make this the one television tuner IC capable of working with receivers fed from antennas or cable hookups. By loading different firmware, the XC3028 can provide television anywhere, eliminating the need to change components. The low-power receiver IC is especially well suited for Universal Serial Bus (USB) based designs that add television receive capability to a desktop or laptop personal computer (PC). Many Asia PC-TV suppliers, like 10moons, Compro, and Kworld, have adopted XCEIVE's silicon tuner for its USB 2.0 television tuner modules for PCs. Such compact USB-based television tuners (Fig. 4) would not be possible using conventional can-type television tuners.

By integrating all necessary components onto a single silicon-germanium (SiGe) BiCMOS chip, the XC3028 television tuner provides repeatable chip-to-chip performance without production tuning. In comparison, can tuners consist of discrete components mounted and interconnected on a printed-circuit board (PCB) and then housed in a metal enclosure. In addition to the electrical tolerances of these individual components, each component exhibits variations due to temperature and time (as well as the PCB) that result in wide variations in final performance which affects manufacturing yields. It is not surprising to find large variations in picture quality for the same model television set manufactured with can tuners, where the frequency response can typically vary several dBs across a manufacturing lot.

The XC3028 is manufactured with a proven 0.181.8-m SiGe BiCMOS process from Jazz Semiconductor (Newport Beach, CA). XCEIVE's foundry partner also fabricates the company's earlier XC2028 television tuner chip, for analog television applications. XCEIVE's proprietary tunable wideband active RF filtering supports the wide input frequency range while the onboard crystal oscillator and PLL circuitry provide frequency stability that is accurate and never in need of alignment. With the combination of a very fast PLL, built-in demodulator and optimized firmware, the XC3028's QuickTuneTM technology can tune to a new channel in 10ms. For anyone who has suffered through the " autoprogram" feature as a new television set tunes through its frequency range in search of available channels, the XC3028 reduces this programming time from minutes to mere seconds.

XCEIVE QuickTuneTM technology will also make picture-in-picture (PIP) something of the past. MultiViewTM is a new feature being integrated in the latest TVs and PC-TVs (see picture). A viewer can view their main program while simultaneously viewing live "PIP" pictures that surround the main picture. They can even switch back and forth between TV programs instantaneously when they see something better on a different channel.

One tuner is used for the main picture and another tuner is used for the "PIP" pictures. To ensure an enriched experience, the surrounding "PIP" pictures must refresh fast enough to appear live which puts a strong demand on the tuner's ability to lock and scan channels quickly. XCEIVE's Silicon TV Tuner is the fastest tuner in the world today. The faster the tuner, the better the viewing experience. Ideally, a separate tuner should be used for each PIP picture to achieve 30frames/ second. However, XCEIVE's QuickTuneTM technology makes MultiViewTM possible without designing in a tuner for each PIP picture. It is the most cost effective way to implement MultiViewTM while giving a refreshing new application to TV and PC-TV suppliers.

The company recently received Imaging Science Foundation (ISF) Research Labs certification for the XC3028 in recognition of the IC's quality and performance levels. In cooperation with Microsoft, ISF is responsible for certifying hardware for Windows XP Media Center Edition. Created in response to customer and partner feedback, the program educates consumers and partners about related components and peripherals that deliver the best experience with a PC running Windows XP Media Center Edition. XC3028 is the first tuner, silicon or can, to have its performance excellence validated by the ISF Research Labs. According to Joel Silver, ISF founder, "Until now, we had not tested a TV tuner that met the standards for ISF certification."

XCEIVE Corp., founded in 2001, is led by a management team that includes Dr. Alain-Serge Porret, vice president of engineering and formerly of the Electronics Laboratory at the Swiss Federal Institute of Technology; Alvin Wong, vice president of marketing and formerly with Infineon Technologies and Philips Semiconductors; Jordan Du Val, vice president of sales and formerly with SpotNet, Telecruz Technologies, S3 Inc, and Genesis Microchip ; and Marcus Tai, vice president of operations and formerly with Alliance Semiconductor, Fairchild Semiconductor, and VLSI Technology. The company is funded by venture capital from leading investment firms, including Alliance Ventures, BA Venture Partners, Ignite Group, and Sequoia Capital.

With growing interest in "television anywhere at anytime," and increasing integration of functions into cellular handsets, it would not be surprising to see the XC3028 (Fig. 5) or its future generations operating in cellular telephones or other portable communications devices, such as personal digital assistants (PDAs). The low-power consumption of the analog/digital television tuner makes it a candidate for true "television on the go" functionality.

XCEIVE Corp., 3900 Freedom Circle, Ste. 200, Santa Clara, CA 95054; (408) 486-5610, FAX: (408) 486-5615, email: [email protected], Internet: