BCM3520

BCM3520 ® ATSC/NTSC/QAM DIGITAL CABLE READY DTV RECEIVER FEATURES • Integrated VSB/QAM QAMLink® receiver 12-bit A/D converter with internal AGC amplifier Full equalizer architecture spans up to –35 to 49 µs delays Direct IF sampled architecture reduces system cost Single IF signal path for QAM/VSB/NTSC to reduce system costs - ITU-T J.83 Annex A/B/C FEC modes - MPEG-2 transport output (serial/parallel) - All-digital clock and carrier recovery - Integrated PLLs to minimize external components - All acquisition times typically less than 50 ms • QPSK out-of-band receiver - 100–200-MHz receiver LO with input AGC and 6-bit A/D - Variable symbol rate QPSK receiver - Digital demodulator, Nyquist filters, tracking loops, and four-tap adaptive equalizer - DVS-167 (Davic™)/DVS-178 (DigiCipherII™) FEC decoder • NTSC/PAL IF Demodulator - Adjacent channel rejection filters - Programmable digital audio trap filter - Programmable group delay compensation filter - Analog Composite Video Baseband Signal (CVBS) output - FM demod output supports internal BTSC stereo decoder, external BTSC stereo decoder (baseband or IF input), or external Zweiton M decoder • Integrated acquisition controller - SUMMARY OF BENEFITS • Complete DTV single chip receiver solution • FCC VSB and Digital Cable Ready • Superior performance under both static and dynamic multipath channel conditions • Integrated NTSC demodulator • BTSC decoder on chip • • • • • Direct interface to CMOS and discrete DTV tuners Reduces system costs through direct IF sampling Single IF path for QAM/VSB/NTSC simplifies board design Smart antenna support Automatic NTSC co-channel interference and RFI rejection filters • Integrated de-interleaver RAM for VSB FEC, and QAM for modes up to J=4 reduces system costs • Analog stereo, mono, or SAP outputs • I2S or baseband multiplexed audio output • On-chip stereo audio DACs • BSC master to control peripherals • EIA/CEA-909 antenna interface • 144-pin LQFP package Plug and Play DTV System Solution Cable ATSC BCM3431 LNA BCM3418 Tuner MPEG Transport Serial/Parallel Composite Video BCM3520 Out-of-Band VSB/QAM OOB/CableCard™ Audio: I2S, L/R, Multiplex Baseband, IF Audio Out-of-band Transport EIA/CEA-909 Smart Antenna Interface OVERVIEW BSC/SPI Host Interface BSC/SPI Slave Interface HAB Acquisition Processor Internal Bus To All Blocks Master PLL 54-MHz 3rd Overtone Crystal Interrupt In-Band Tuner In-Band AGC In-Band AFT 16-1024 QAM Advanced Receiver OOB Tuner OOB AGC OOB VCO OOB AFE PGA 6-Bit A/D AGC Control VCO ITU-T J.83 Annexes A/B/C FEC In-Band AFE PGA 12-Bit A/D AGC Control ATSC 8/16 VSB Advanced Receiver ATSC FEC Output Interface MPEG Transport 10-Bit D/A NTSC IF DEMODULATOR 10-Bit D/A Composite NTSC IF Audio I2S OOB QPSK Receiver BTSC Decoder HiFi DAC L/R Audio or Multiplexed Baseband Audio DVS-167 FEC DVS-178 FEC BSC Master Interface GPIO/GPO Interface EIA/CEA-909 Interface OOB Output Interface OOB Transport for CableCard/POD BCM3520 JTAG Interface Tuner/Peripheral Control GPIO GPO Antenna Control JTAG Controller BCM3520 Block Diagram The BCM3520 is a ATSC/NTSC/QAM Digital Cable Ready DTV receiver that contains a digital receiver that is compatible with both North American digital cable television and digital terrestrial broadcast television standards. This receiver is capable of receiving all standarddefinition and high-definition digital formats (SDTV/HDTV). It also contains an IF demodulator compatible with the NTSC video standard. The output of the IF demodulator can be directed to an external BTSC or Zweiton M decoder, or can be sent to an on-chip audio decoder. The onchip audio decoder is fully compliant with the BTSC audio standard. An out-of-band QPSK receiver is also contained to meet the needs of the CableCard specification. The BCM3520’s digital receiver and NTSC demodulator accepts an analog signal centered at the standard television IF frequencies, and amplifies and digitizes this signal with an integrated programmable gain amplifier and 12-bit A/D converter. The output of the A/D is sent to the receiver and demodulator. The digital receiver consists of a QAM demodulator and a VSB demodulator. Each demodulator contains adaptive filters that remove multi-path propagation effects, NTSC cochannel interference, and RFI interference. The output of the VSB demodulator goes to an ATSC A/53 coding forward error corrector (FEC), with integrated trellis and Reed-Solomon decoder. The output of the QAM demodulator goes to an ITU-T J.83 Annex A/B/C coding FEC. The output of either QAM or VSB FEC is delivered in either parallel or serial MPEG-2 transport format. The NTSC demodulator filters and demodulates the analog NTSC and FM audio signals and delivers a composite output via an on-chip 10-bit DAC. An IF modulated audio output is also provided via a second on-chip 10-bit DAC. An on-chip BTSC decoder handles the decoding of the base-band multiplexed audio from the IF demod, providing an stereo left/right, mono, or SAP output via a pair of high precision HiFiDACs. All gain, clock, and carrier, acquisition, and tracking loops are integrated on-chip as are the necessary phase-locked loops, referenced to a single external crystal. Chip configuration, channel acquisition, and performance monitoring functions are conducted by the on-chip acquisition processor using Broadcom-provided software. Broadcom®, the pulse logo, QAMLink® , Connecting everything®, and the Connecting everything logo are among the trademarks of Broadcom Corporation and/or its affiliates in the United States, certain other countries and/or the EU. Any other trademarks or trade names mentioned are the property of their respective owners. ® BROADCOM CORPORATION 16215 Alton Parkway, P.O. Box 57013 Irvine, California 92619-7013 © 2006 by BROADCOM CORPORATION. All rights reserved. 3520-PB05-R 10/23/06 Phone: 949-450-8700 Fax: 949-450-8710 E-mail: info@broadcom.com Web: www.broadcom.com