PRODUCT
Brief
BCM3137
BCM3137 FEATURES SUMMARY OF BENEFITS
•A high-performance, integrated solution for upstream
demodulation in cable data, video and telephony
applications
•Provides full DOCSIS/EuroDOCSIS compliance for
use in Cable Modem Termination Systems (CMTS)
•Seamless integration with BCM3210B CMTS Media
Access Controller (MAC)
•Applicable to digital CATV reverse-channel receiver
•Unprecedented integration of three on-board ADCs
•Reduces overall system cost
•Increases channel density per card
•Simplifies RF frontend design
•Enables power estimation of the entire upstream band
•Improved ability to control external VGAs/PLLs
through integrated serial/parallel interface
•Extraordinary handling of burst-to-burst variations
in excess of 20 dB
•Supports random burst arrival
•Improved ability to remove channel impairments
through integration of an adaptive equalizer
•Maximum baud rate flexibility with full
programmability from 100 kBaud to 5.12 MBaud
•The Broadcom BCM3137 is a headend QPSK/QAM
burst receiver for CMTS applications
•DOCSIS/EuroDOCSIS, IEEE 802.14, DAVIC and DVB-
compliant
•Programmable Demodulation: QPSK/16 QAM
•Variable symbol rates from 100 kBaud up
to 5.12 MBaud
•Analog front-end featuring dual gain stages and dual
10-bit ADCs, plus a 6-bit ADC to estimate wideband
channel
•Fast burst acquisition: preamble size as small
as 4 bytes
•Programmable components include:
•Flexible symbol demapping: Differential /
Non-Differential
•RS decoder block size (N), GF (256), T = 1 to 10
•Last RS codeword size: fixed or shortened
•23-bit derandomizer: polynomial, seed, type
•Derandomizer location: before/after RS decoder
•Internal burst FIFOs for receive rate de-coupling
•Choice of serial data receive interfaces
•JTAG Test Interface
•100-pin PQFP Package
DOCSIS/EuroDOCSIS-compliant Cable Modem Ter mination System Block Diagram
BCM3137
UNIVERSAL BURST RECEIVER
PA
CLOCK DATA
CLOCK DATA
PCI
Backbone
LPF
44 MHz IF
5-65 MHz VGA RF
Tuner SAW LPF
PCI
Interface
100Base-T
Ethernet
Pentium
PC
BCM3137
Burst Demod
1-8 Channels
BCM3033
QAM
Modulator
BCM3210B
MAC
BCM3137 OVERVIEW
The Broadcom BCM3137 QAMLink®Universal
QPSK/16 QAM Burst Receiver is a complete single-chip cable
network receiver, that accepts QPSK and 16 QAM upstream
burst data in a frequency-agile, time-division multiple access
(TDMA) scheme. An analog front-end (AFE), a QAM
demodulator and an FEC decoder are integrated on this single
chip. The AFE performs coarse gain setting and A-to-D
con version on either an IF input or baseband I/Q inputs. A digital
down-mixer translates the input spectral center to true DC.
The I and Q samples pass through dual decimators and square-
root raised cosine filters with an excess bandwidth α= 0.25.
Fast burst detection and acquisition are performed on the
preamble with programmable length and pattern. The chip
incorporates unique word (UW) detection in the preamble
process to delineate the packet and resolve phase ambiguity.
Carrier phase offset is removed by a derotator. An adaptive
equalizer characterizes the RF channel response and removes
inter-symbol interference (ISI) caused by micro-reflections.
The FEC decoder consists of a programmable derandomizer and
a programmable RS decoder. FIFO buffers provide input/output
data rate de-coupling for the FEC decoder.
The BCM3137 delivers the recovered data stream and accepts
receiver control inputs through a receive interface linked to an
MCNS MAC chip. The BCM3137 prepends ranging and data
information to each received code word and packet for
processing by the BCM3210B. An ATM UTOPIA-like receive
interface is also supported in a bit-serial style. The BCM3137
can be configured through either an SPI or I2C-compatible
serial interface.
The BCM3137 represents a highly-integrated, mixed-signal
solution that significantly increases the channel density per line
card for CMTS implementations. When combined with the
BCM3033 QAMLink Universal Modulator and the BCM3210B
QAMLink CMTS Media Access Controller, these chips are an
ideal solution for cable headends. A complete CMTS reference
design (BCM93210B), which integrates these three chips, is
available from Broadcom, providing a complete development
platform for a multi-channel, DOCSIS/EuroDOCSIS-compliant
Cable Modem Termination System.
Phone: 949-450-8700
FAX: 949-450-8710
Email: info@broadcom.com
Web: www.broadcom.com
Broadcom®, the pulse logo®, QAMLink®and Connecting EverythingTM are trademarks of
Broadcom Corporation and/or its subsidiaries in the United States and certain other countries.
All other trademarks are the property of their respective owners.
BROADCOM CORPORATION
16215 Alton Parkway, P.O. Box 57013
Irvine, California 92619-7013
© 2002 by BROADCOM CORPORATION. All rights reser ved.
3137-PB04-R-4.19.02
2
8
8
2
2
10
10
10
3
10
AFE
(PGA's,
ADC's)
Digital
Complex
Mixer
Variable
Decimator Matched
Filter
De-
randomizer
RS
Decoder
Multi-Type Burst
Configuration
Banks
Channel
Charact.
Storage
FEC Interface
and FIFO's
Phase
Derotator
DDFS
Adaptive
Equalizer
Receive
Interface
Matched
Filter
Ranging
Block Preamble
Process Tracking
Loops Bypass/
Probe/
External
Control
JTAG PLL & Clock Generation Micro Interface
Variable
Decimator
A_SP/N
A_IP/N
A_QP/N
SMPLCK
RXDATA
BITCK_RSOB
BLKDV_REMP
MSCLK_RXNW
MAPDV_RXEN
MPCLK_RCLK
MAPDATA
PIOA[9:0]
PIOB[9:0]
TPA[7:0]
TPB[7:0]
TCK TMS TDI 12C
SPI ADDR0
SS ADDR1
MISO ADDR2ADDR3 TM[2:0]SDA
MOSI
SCL
SCK
TDO PLLBYP XTALI XTALO RESET
