Zarlink tuner chipset reduce STB size, cost

Zarlink Semiconductor Inc. has made available a two-device chipset for tuning analog and digital RF cable TV signals, while allowing designers of multiservice cable STBs to shrink tuner designs by 50 percent and reduce tuner costs by up to 20 percent.

The RF cable tuner chipset is comprised of the company's SL2101 broadband tuner, which performs frequency up-conversions, and the ZL10100, which handles frequency down-conversions and IF amplification.

The chipset reduces the size, BOM, and production costs of high-performing cable tuners by implementing active RF and IF amplification circuitry directly in silicon. The company claims that the RF and IF amplification circuitry in the ZL10100 device eliminates up to 40 external components from high- performance, double-conversion tuner designs.

The SL2101 and the ZL10100 are claimed to exceed the performance specifications of the DOCSIS 1.1 OpenCable standard and satisfy the U.S. FCC Part 15B EMI requirements.

The ZL10100 down-converter is an RF mixer-oscillator with an operating range of 1GHz to 1.3GHz. It is coupled to the differential IF amplifier, which provides a differential 75-ohm output drive capable of interfacing directly with standard SAW filters. The ZL10100 provides 24dB of gain and is compatible with IF output frequencies between 30MHz and 60MHz.

It also features an on-chip, I2C bus-controlled PLL frequency synthesizer designed to deliver low phase noise. At 10kHz, the free-running phase noise of the device is typically less than -93dBc/Hz.

The SL2101 is built in a SiGe process, while the ZL10100 uses a high-speed bipolar process. Both chips are packaged in miniature, 28-pin SSOPs. In volumes of 100k, the SL2101 is priced at $1.70 and the ZL10100 at $1.89.