BCM3138 Datasheet, PDF (2/2 Pages) Broadcom Corporation. – DUAL UNIVERSAL ADVANCED TDMA PHY-LAYER BURST RECEIVER

OVERVIEW
DAP/N
A_IP/N
24
I
AFE
(ADC
2
and
MUX)
Q
Digital
Complex
Mixer
FFT STRT
FFT CLK
FFT DATA
FFTDV
DBP/N
FFT
Processor
24
DDFS
B_IP/N
2
CKIP/N
2
JTAG
Variable
Decimator
Matched
Filter
Variable
Decimator
Matched
Filter
QAM
Burst
Demodulation
Adaptive
Equalization
and
Ingress
Cancellation
Deinterleaver
FEC Interface
and FIFOs
MAC/
PHY 4
Interface
Ch-A
Ranging
Block
Preamble
Process
Tracking
Loops
De-
scrambler
RS
Decoder
Receive Channel B
MAC/PHY
Interface
Ch-B
13
PLL & Clock Generation
Micro Interface
Bypass/
Probe
6
Exit Control
6
5
4
24
RACLK
RASOBN
RADV
RADATA[3:0]
RADATAP
MSCLKA
MAPCLKA
MAPDVAN
MAPDATA
INTAN
EXCTLA[5:0]
EXCTLB[5:0]
TCK TMS TDI TDO PLLBYP XTALI XTALO RESET
I²C SCL SDA ADDR0 ADDR1 ADDR[6:2] TM[3:0] TPA/B[11:0]
SPI SCK MOSI SS MISO
The BCM3138 QAMLink® Universal QPSK/QAM burst receiver is a
highly integrated solution that significantly decreases the board space
and cost of demodulators in digital cable modem head-ends applications.
The BCM3138 provides two independent cable network receivers that
accept QPSK and m-QAM burst data in frequency-agile, time-division
multiple access (TDMA) schemes. Advanced features in the BCM3138
include an analog front end (AFE), a QAM demodulator, a generalized
equalizer and an enhanced Reed Solomon (RS) FEC decoder with
dynamic deinterleaving.
The AFE provides coarse gain setting and A-to-D conversion (ADC) on
either an IF input or baseband I/Q inputs. When the internal ADC is
bypassed, the on-chip digital mixer translates the desired signal at RF to
true DC where the I and Q samples pass through variable decimators and
matched raised-cosine filters. The BCM3138 incorporates unique word
detections of programmable length and pattern in the burst preamble for
signal acquisition as fast as 16 symbols. An adaptive equalizer and
ingress canceller characterizes the RF channel response, cancels ingress
noise and removes inter-symbol interference (ISI) caused by micro-
reflections in the channel. The FEC decoder consists of a programmable
de-randomizer, a programmable RS decoder with T values
programmable up to 16 and a byte deinterleaver with burst-by-burst
reconfiguration capability.
The BCM3138 delivers the recovered data stream and accepts receiver
control inputs through a receive interface linked to a DOCSIS MAC chip
such as the BCM3212. The BCM3138 prepends ranging and data
information to each received code word and packet for processing by the
BCM3212. The BCM3138 can be configured through either an SPI or
I2C-compatible serial interface.
The BCM3138 is a highly integrated, mixed-signal and cost-effective
device providing a worldwide solution for burst receiver applications.
The dual receiver design of the BCM3138 is packaged in a 208-pin
PQFP, enabling a significant increase upstream channel density for
head-end based CMTS equipment. The BCM3138, combined with the
BCM3034 QAMLink® Universal Modulator and the BCM3212
Advanced QAMLink® CMTS MAC, provides a complete solution for
advanced cable headend equipment.
Broadcom^®, the pulse logo, and Connecting everything^® are trademarks of Broadcom Corporation and/
or its subsidiaries in the United States and certain other countries. All other trademarks mentioned are the
property of their respective owners.
®
BROADCOM CORPORATION
16215 Alton Parkway, P.O. Box 57013
Irvine, California 92619-7013
© 2004 by BROADCOM CORPORATION. All rights reserved.
3138-PB04-R
07/01/04
Phone: [phone]
Fax: [phone]
E-mail: [e-mail]
Web: www.broadcom.com