BCM3033 Datasheet, PDF (2/2 Pages) Broadcom Corporation. – QAMLINK UNIVERSAL MODULATOR

BCM3033 OVERVIEW
8
PS_IN[7:0]
PS_CLK
PS_VALID
PS_SYNC
RAM_CTRL
26
DCII
DVB
DAVIC
Encoder
Nyquist
Filter
α = .12-.18
Nyquist
Filter
α = .12-.18
Interpolation
Filter
QDDFS
Interpolation
Filter
JTAG[3:0]
JTAG Interface
PLL / Clock Generation
x
sin x
D/A
A_IF+/-
D_IF[9:0]
M-Bus/SPI
Interface
DAC_CLK
MICRO[4:0]
The BCM3033 QAMLink Universal Modulator is a highly-
integrated solution that significantly decreases the board space and
cost of modulators in digital cable TV headends, digital cable
modem headends, digital microwave radio, SMATV and MMDS
applications. Integrated features in the BCM3033 include an
integrated ITU-T J.83 Annex A (DVB/DAVIC/ IEEE802.14),
Annex B (DigiCipher^® II/SCTE/DOCSIS/EuroDOCSIS/
IEEE802.14), and Annex C (Japan) FEC encoder, a QAM
modulator and a D/A converter. The encoder provides coding gain
and burst error correction and can be programmed to comply with
the ITU-T J.83 Annex A, Annex B and Annex C coding standards.
Baseband filtering and quadrature upconversion of the resulting
signal is provided by the integrated QAM modulator, which can
achieve IF frequencies of up to half the output sample rate.
The QAM modulator is rate adaptable up to 7 megabaud and
supports 4-, 16-, 32-, 64-, 128-, and 256-QAM. triple
linear-phase square-root Nyquist baseband filters are in the
QAM modulator and have a programmable excess bandwidth
factor of 12%, 15% or 18%. The QAM modulator also has an
X/sinX filter that compensates for DAC distortion. The
integrated DAC in the BCM3033 is a 10-bit, 114-MS/s DAC
with differential analog outputs.
Operation of the BCM3033 involves a serial or parallel bit
stream input that can be passed through the FEC encoder or
directly to the modulator. The resulting data is interpolated,
filtered, and modulated to the IF carrier. The modulator provides
a 10-bit output at the chosen sample rate, which is converted to a
2-Vpp differential analog output waveform by the integrated
10-bit D/A converter.
The BCM3033 is a flexible, cost-effective worldwide solution.
Because the chip accepts variable data rates and supports
multiple digital transmission standards, manufacturers need to
develop only one modulator for worldwide use. The integrated
feature set in the BCM3033 significantly reduces the board
space in modulators, giving manufactures a chip solution that is
both cost effective and easy to use.
Broadcom^®, the pulse logo, QAMLink^® and Connecting everything^® are trademarks of
Broadcom Corporation and 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 reserved.
3033-PB04-R 11.20.02
Phone: [phone]
FAX: [phone]
Email: [e-mail]
Web: www.broadcom.com