audio/videoZONE Products for the week of May 24, 2004
STMicroelectronics Says . . .
STB6000: Single-Chip Silicon Tuner Reduces the Cost
of Satellite TV Connections
Set-Top Box front end is a partner for ST's widely used STV0299
satellite demodulator
STMicroelectronics announced a new single-chip silicon tuner, the STB6000, which is designed to replace complex discrete component tuners in Set-Top Boxes (STBs) used for receiving digital TV or web-based material via satellite. Cost savings will be achieved in STB production through the lower component count and simplified printed circuit board design.
ST is the world's largest supplier of silicon chips for set-top boxes1, including satellite, cable and terrestrial services. Price is the overriding factor for consumers in these markets and the new device will help STB manufacturers to further reduce their costs by replacing the discrete tuner circuitry of existing products with a single 32-lead package, requiring minimal supporting components. In addition it will eliminate the need for specialist RF expertise as the RF processing circuitry is integrated onto the chip.
Whilst the tuner is a standalone functional block, it is intended to form part of a co-ordinated chip-set with ST's well established STV0299 multistandard demodulator, which is very widely used in satellite TV applications. Like the STV0299, the STB6000 is programmed through a simple two-wire serial interface.
"By introducing the STB6000 our customers can now use ST silicon products to process the broadcast signal at every stage in satellite STBs," said Armando Caltabiano, General Manager of the Satellite and Terrestrial Business Unit of ST's Set Top Box Division. "The pairing of the STB6000 and STV0299 perfectly complements our range of MPEG decoders and gives us an opportunity to increase our share of the satellite STB front-end market."
The STB6000, which has been developed in co-operation with RFMagic Inc.,
is suitable for use in satellite STBs throughout the world; it supports
the DVB (Digital Video Broadcasting), DIRECTV and VSAT (Very Small Aperture
Terminal) protocols. The tuner will be of interest to NIM (Network Interface
Module) manufacturers - who supply assembled and set up tuner/demodulator
modules to STB producers - as well as to those producers who assemble their
own on-board tuners; currently around half of the STBs produced worldwide
contain third party modules.
analogZONE Says...
One doesn't expect major jumps in RF architecture from STMicroelectronics, but the fact that they have used the extreme talents of the RFMagic team in San Diego is a tribute to the company's ability to understand when it makes sense to go out of house.
The result is a product that will change the face of the front-end of satellite receivers.
The input range of the STB6000 is from 950 MHz to 2150 MHz with the single-ended RF input going directly to a variable-gain LNA that also converts the signal to a differential format. Separate I and Q paths each mix the signals directly down to baseband where they pass through separate VGAs, low-pass filtering and a stepped-gain amplifier stage to provide buffered differential I and Q outputs. AGC (control sourced off-chip) is applied to both the input LNA and the VGA after down-conversion. The bandwidth of the low-pass filter is variable remotely from the 2-wire bus. The direct conversion technology used is the simplest available with on-chip dc offset cancellation.
The LO is derived from an on-chip synthesizer and PLL from an external crystal. The crystal oscillator output is also available as a buffered output to drive other devices.
Symbol rates up to 45 Msymbols/s are supported, allowing for the part to be used for HD satellite channels, and the outputs are ideal for driving STM's STV0299 BPSK/QPSK demodulator -- the most popular solution in use today.
Simplifying the front-end of the satellite receiver chain is going to allow the remainder of the receiver/STB to be developed by non-RF design engineers; this part is going to be a huge success story and will reduce both the cost and complexity of satellite receivers.
The STB6000 is in production in QFN-32 and is priced at $2.00 in 1000-piece lots.