Zarlink Semiconductor has added what it claims is the industry's fastest-scanning, lowest-power channel demodulator to its successful family of radio frequency (RF) chips for digital satellite TV systems.

An official release informs that Zarlink's ZL10312 chip is aimed primarily at set top boxes (STBs) sold in Asia and the Middle East that receive "free-to-air" digital TV channels on satellite broadcast bands. The demodulator is also suitable for the European and US satellite STB markets.

The ZL10312 device, combined with Zarlink's SL1925/1935 tuner chips, offers manufacturers a complete RF subsystem for tuning, scanning, decoding, and demodulating digital satellite TV signals. Around 70 per cent of the digital satellite STBs manufactured in China use Zarlink tuners, the release states.

To provide consumers with STBs that are easier to use, manufacturers want demodulators that quickly scan and lock onto digital satellite TV channels with little or no user input. The ZL10312 demodulator automatically scans the complete satellite broadcast band in minutes - the industry's fastest auto- scan performance. In comparison, competing demodulator chips can take hours to perform the function, and require consumers to input such variables as frequency, code rate, and symbol rate the company claims.

Zarlink has stated that its new satellite demodulator is the lowest-power chip in its class, with consumption of only 300 mW (milliwatts). As STBs shrink in size, heat-sensitive RF tuner and demodulator chips are being packed into smaller areas. The ZL10312 demodulator minimises heat generation, improving RF performance and field reliability.

Zarlink's ZL10312 chip is a digital satellite demodulator that supports quaternary phase shift keying and bipolar phase shift keying modulation schemes. The device uses advanced digital filters to detect and decode symbol rates from 1-45 MS/s (megasymbols per second), allowing it to process a flexible range of satellite channels without external components.

An on-chip hard-wired controller helps the ZL10312 device achieve its ultra-fast channel scanning capability. The controller saves time by implementing scan routines at high speeds with little intervention from an external processor. This allows manufacturers to minimise software overhead and reach markets more quickly - the release states.