ST公司的STi5197是低成本QAM解调器和MPEG2译码器, 标准清晰度(SD) STB系统级芯片( SoC). STi5197集成了QAM解调器,音频/视频译码,视频处理,图像和显示,先进的安全性,STB外设,音频/视频DAC,数字音频/视频输出,USB 2.0主控制器/UPI以及以太网MAC MII/RMII,形成完整的STB解决方案,非常适合于基于MPEG2的线缆网络应用.本文介绍了STi5197的主要特性,方框图以及多种应用框图包括MPEG2广播有线STB方框图, 双调谐混合/DVR有线STB方框图,以及MPEG2交互式有线STB方框图.
Low-cost QAM demodulator and MPEG2 decoder for set-top box applications
The STi5197 uses state of the art process technology to provide an ultra low cost, full
featured, SD set-top box SOC. It is a highly integrated solution combining QAM
demodulation, audio/video decoding and applications processing into a single chip, suitable for MPEG2 based Cable networks worldwide.
The STi5197 provides a solution for operators to specify a range of low cost SD STBs
including low cost Zappers, Interactive STBs and DVR-capable STBs, with content delivery using broadcast or broadband networks, or both (Hybrid STBs).
The STi5197 is optimized for secure Pay-TV applications with integrated DVB, DES, Multi2 and ICAM descramblers and Smart Card interfaces. It also has advanced security features normally found in mid-to-high end devices to further safeguard operator and content investment.
The STi5197 offers enhancements in performance, features and integration to current users of ST’s MPEG2 SD family of audio/video decoders and QAM demodulators, whilst reducing cost and time-to-market for the next generation of deployments. Few external components are required to realize a complete STB solution, resulting in very low BOM cost.
STi5197主要特性:
The STi5197 integrates in a single IC, QAM demodulation, FEC, Multi-stream transport
demux, applications CPU, audio/video decode, video processing, graphics and display,
advanced security, STB peripherals, audio/video DACs, digital audio/video outputs, USB 2.0 host controller/ULPI and Ethernet MAC MII/RMII.
QAM demodulator/FEC
– High-performance 12-bit A/D converter suitable for direct IF architecture in all QAM (quadrature amplitude modulation) modes
– Demodulation and decoding of ITU-T J.83-Annexes A/B/C and DVB-C bit streams
– Full digital demodulation
– Variable symbol rates
– Supports 16, 32, 64, 128 and 256 point constellations
– Front derotator for better low symbol rate performance and relaxed tuner constraints
– Integrated matched filtering
– Robust integrated adaptive pre and post equalizer
– On-chip Forward Error Correction (FEC) supporting Annexes A, B and C, with ability to bypass individual blocks
– Two AGC outputs suitable for delayed AGC applications (sigma-delta outputs)
– Integrated signal quality monitors, plus lock indicator
– Processes Japanese transport stream multiplex frame (TSMF)
High performance CPU for applications, middleware, drivers, audio decoding and network protocols
– ST40-300, dual-issue, applications CPU
– FPU, MMU, 32KI, 32KD 2-way set associative caches
– Supports OS21 and Linux operating systems
– Target speed > 350 MHz delivering >580DMIPs
Single, 16-bit wide, unified local memory interface
– Supports both SDR SDRAM up to 166 MHz and DDR1 SDRAM up to 200 MHz
MPEG2 MP@ML video decoder, dual SD decoding/PIP capable
Audio sub-system
– MPEG-1 layers I/II decoding
– MP3 decoding
– Dolby Digital 5.1 decoding and down mix to Stereo/Pro-logic
– Concurrent decoding of audio description
– Optional feature: BTSC stereo encoding
– PCM mixing with sample rate conversion
– Simultaneous audio decode and output of Dolby streams on S/PDIF
IEC60958/IEC61937 digital audio output interface
– Integrated stereo audio DAC system
Programmable external memory interface
– Four separately configurable banks, 8/16-bits wide
– SRAM, peripheral, NOR Flash, NAND Flash, Burst Mode Flash support
– Boot from NOR or NAND Flash
– Support for DVB-CI module host interface
– Fast synchronous MPX (master) protocol on EMI for interface to STv0498 Triple
QAM/DOCSIS cable modem IC
Interface to, and boot from, Serial FLASH via high speed SPI interface
– High speed Dual I/O support
Graphics/Display processing
– High performance 2-D graphics blitter accelerator and display compositor, Link list
control
– Multi-plane video/graphics composition with alpha blending, typical four-plane use
case (background color + still plane + video plane + OSD plane), and integrated
Tile RAM bandwidth saver for enhanced performance
– High quality horizontal and vertical reformatting and resizing, with sample rate
conversion/filtering for video and graphics
– 8 bpp CLUT and 16 bpp true color graphics formats supported
– Advanced anti-flicker filtering
– De-interlacing SD to 480p/576p for HDMI output
Display output
– PAL/NTSC/SECAM encoder
– Encoding of CGMS, Teletext, WSS, VPS, Closed caption
– Macrovision 7.1D copy protection
– Four 10-bit video DACs, outputting RGB/CVBS/YC analog video signals
– High drive-capability on one of the video DACs for CVBS output without buffering
– 8-bit digital video output (DVO), compliant with ITU-R BT 601/656 formats
– 54 MHz output data rate on DVO supporting 480p/576p output over 8 bits
DVR capable transport sub-system
– TS reception from internal QAM demodulator
– External TS interface for a second stream input from external tuner/demodulator
– Dual internal TS from memory for network/IP stream input and DVR playback
– TS output for routing to DVB-CI module
– DVB-compliant, triple-stream transport de-multiplexing
DVB, DES, Multi2 descrambling
ICAM2.2 NDS Conditional Access
DVR supported with HDD attachment via EIDE (PIO mode) or USB 2.0
Multi-channel flexible DMA Controller
Connectivity
– 10/100 Ethernet MAC with MII/RMII interface to external PHY
– USB 2.0 Host Controller with ULPI interface to external PHY
On-Chip STB Peripherals
– Two Smart Card Interfaces with integrated clock generation
– Four UARTs with Tx and Rx FIFOs
– Three SSCs for I²C/SPI master/slave interfaces, one of which can be dedicated for
tuner control with minimum tuner disturbance
– Five 8-bit GPIO banks with alternate functions
– Infrared transmitter/receiver
– PWM
– CEC line controller
System services
– All clocks generated from a single external crystal
– Integrated DCO for clock recovery
– Low power/RTC/watchdog controller
– JTAG/TAP interface
Advanced security
– Secure control words
– Code authentication
– JTAG interface locking
– DVR copy protection
On chip 1V (nominal) voltage regulator
Two package options
– 23mm x 23mm. Full Specification, with EMI
– 15mm x 15mm. Full Specification, except no EMI and boot from Serial FLASH
Only
图1. STi5197方框图
图2.STi5197 MPEG2广播有线STB方框图
图3.STi5197 带HDD MPEG2双调谐混合/DVR有线STB方框图
图4.STi5197 带DVB-CI插座的MPEG2广播有线STB方框图
图5.STi5197 嵌入DOCSIS有线调制解调器的MPEG2交互式有线STB方框图
