B C M 3 1 1 6 F E A T U R E S
RJ45
Connector
Coax
Connector
RAM
ROM
Tuner
Diplex
Filter
BCM3037
Upstream
QPSK/16-QAM
Modulator
BCM3220
MAC
Microcontroller
w/Enet MAC
10BASE-T
Transceiver
CLOCK
DATA
CLOCK
DATA
LPF
SAW
PA
5-42 MHz
44 MHz IF
54-860 MHz
Gain Control
BCM3116/3118
QAM Receiver
w/FEC
DOCSIS-compliant Cable Modem Block Diagram
Fully-integrated, DOCSIS-compliant solution for cable
modems and cable-TV set-top boxes
Enables the industry's lowest cost, least complex system
Simplifies system, board and software design through the
integration of analog components
Reduces power consumption
Enhanced digital adaptive equalization
Robust performance in the presence of multipath at high order
QAM constellations
Superior echo cancellation capability for both wired
and wireless applications
Seamless integration with key subscriber cable modem
components:
BCM3037: QAMLink QPSK/16-QAM Burst Modulator
BCM3220: QAMLink Media Access Controller (MAC)
S U M M A R Y O F B E N E F I T S
B C M 3 1 1 6 Q A M L I N K TM D O C S I S R E C E I V E R
PRODUCT
Brief
B C M 3 1 1 6
Downstream QAM Receiver for North American set-
top box and DOCSIS cable modem applications.
Integrated QAMLink receiver with forward error
correction (FEC)
5.059641/5.360537 MBaud variable symbol rate
Supports 64 and 256-QAM
Digital demodulator, Nyquist filters, tracking loops, and 32-tap
adaptive decision feedback equalizer
Digital derotator for wideband carrier phase tracking
ITU-T J.83 Annex B-compliant FEC decoder
16-state trellis decoder
Reed-Solomon (n,k) = (128,122); t = 3
Programmable convolutional deinterleaver, I*J <128 with
internal RAM, I*J>128 with external RAM
IC or SPI-compatible microcontroller interface
On-chip generation of all clock and control signals
3.3V operation
JTAG Test Interface
100-pin PQFP
The BCM3116 QAMLink Receiver is a fully asynchronous
design with an integrated FEC and 10-bit analog-to-digital
converter. It provides a complete digital transmission solution
for cable modems, cable-TV set-top boxes and digital microwave
radios. Its bandwidth-efficient feature set expands the existing
potential bandwidth of a standard analog network and provides
operators with reliable, error-free transmission.
The BCM3116 accepts a modulated data stream at up to 38.8
Mbps and delivers a demodulated, equalized and error-corrected
output data stream. The receiver integrates a 10-bit A/D
converter, a 256-QAM demodulator with square-root raised-
cosine receive filters, a 32-tap adaptive equalizer with an
embedded phase recovery derotator, acquisition and tracking
loops, and a forward error correction (FEC) decoder. The FEC is
ITU-T J.83 Annex B, DOCSIS, DigiCipher II, IEEE 802.14,
and SCTE DVS-031-compliant.
The analog IF waveform is fed into the chip, where it is sampled
by the integrated A/D converter, digitally mixed to baseband and
filtered by dual square-root Nyquist filters. Inter-symbol
interference is then removed by the adaptive decision feedback
equalizer (DFE). A decision slicer, which supports constellations
up to 256-QAM, formats the equalized data which is then fed
into a trellis decoder, derandomizer, deinterleaver, and Reed-
Solomon decoder. The final error-corrected output is delivered in
non-MPEG or in MPEG-2 transport format.
Optimized for high-volume manufacturing, the BCM3116
represents a highly integrated solution that reduces the system-
level chip count, the cost and the complexity associated with
manufacturing RF receivers. When combined with the BCM3037
QAMLink QPSK/16-QAM Burst Modulator and the BCM3220
QAMLink Cable Modem MAC, the BCM3116 is an ideal
solution for two-way RF cable set-top boxes and cable modems.
B C M 3 1 1 6 O V E R V I E W
For more information please contact us at:
Phone: 949-450-8700, FAX: 949-450-8710
Email: info@broadcom.com
Visit our web site at: www.broadcom.com
2000 BROADCOM CORPORATION
3116-PB02-R-04.24.01
Broadcom
and the pulse logo are registered trademarks of Broadcom Corporation.
QAMLink is a trademark of Broadcom Corporation.
DigiCipherII is a registered trademark of General Instrument Corporation.
BROADCOM CORPORATION
16215 Alton Parkway, P.O. Box 57013
Irvine, California 92619-7013
24-tap
DFE
4
Phase
ROM
sin
n
cos
n
4
10
MICRO[3:0]
A_IF
Q
IF_OSC
P_CLK
P_DATA
P_SYNC
Acquisition/Tracking Loops
and Clock Generation
M-Bus/SPI
Interface
Nyquist
=.12,.18
RF[7:0]
Deinterleaver
RAM
Phase
Recovery
and
8-tap
FFE
10-bit
A/D
Nyquist
=.12,.18
RAM_CTRL
Variable
Rate
Demod
AGC_CTRL
Tuner
Control
BAUD_CTRL
JTAG
P_VALID
P_ERR
GEN_CTL
JTAG[3:0]
ITU-T
J.83
Annex B
FEC
Decoder
PDF 
ZIP