BCM3250 Datasheet, PDF (1/2 Pages) Broadcom Corporation. – QAMLINK ADVANCED SER-TOP BOX SINGLE-CHIP FRONT-END

BCM3250
®
BCM3250 QAMLINK^® ADVANCED SET-TOP BOX SINGLE-CHIP FRONT-END
FEATURES
SUMMARY OF BENEFITS
• Two complete QAMLink variable symbol rate receivers (in-
band video and DOCSIS/EuroDOCSIS IP data receive
channels)
• Dual 10-bit A/D converters with input AGC amplifiers
• Dual 1-7 Mbaud 256-QAM receivers
• Dual ITU-T J.83 Annex A/B/C compatible FEC decoders
• QPSK out-of-band receiver
• 100 – 200 MHz LO with AGC and 6-bit A/D converter
• DigiCipher II®/DVB/DAVIC FEC decoder
• Upstream QPSK/16-QAM transmitter
• 0 – 65 MHz direct RF output
• Programmable Starvue II/DOCSIS/EuroDOCSIS/DVB/DAVIC
FEC encoder
• 10-bit D/A converter with output power control interfaces
• DOCSIS/EuroDOCSIS media access controller (MAC)
• DOCSIS/EuroDOCSIS version 1.1 based
• Extensions for fragmentation and concatenation
• Support for enhanced Quality of Service (QoS) for Voice over
IP (VoIP) applications
• DAVIC media access controller (MAC)
• DAVIC 1.2/1.5 compliant
• Support for 1.5 Mbps and 3 Mbps on both upstream and
downstream
• Parsing, CRC, and ATM cell extraction
• Hardware SAR engine
• Both processor interface and PCI 2.2
• Direct interface to VoIP DSP
• Represents a complete solution for interactive set-top box
front-end, including cable modem functions.
• Universal front-end supports the ITU-T J.83 Annex A/B/C as
well as OpenCable, DOCSIS/EuroDOCSIS and DVB/DAVIC.
• DOCSIS/EuroDOCSIS 1.1-based media access controller
(MAC) supports Voice over IP and high-speed Internet access
capability.
• DAVIC 1.2/1.5 MAC supports conditional access systems and
lower data rate services.
• BCM3250, together with BCM7020/BCM7030 Video Decoder
and Graphics Engine, provide a two-chipset solution for
OpenCable applications.
• Includes second in-band channel pass through for picture-in-
picture functionality and multiple camera angles.
• Integration of all analog functions leads to lower system cost
and improved performance.
• Single upstream transmitter is shared between modem and
upstream interactive video commands, eliminating the need
for a second upstream channel.
• Integrated peripheral control unit supports required set-top
box peripherals without additional external devices.
Interactive Set-Top Box System Block Diagram
Analog V ideo
Cable
Plant
Dual
Tuner
with
Diplex
Filter
IP Data Channel
Video Channel
Out-of-Band Channel
Upstream T ransmitter
BCM3250
QAMLink^®
Advanced
Set-top Box
Single-Chip
Front-End
BCM7038 Dual HD decoder
MIPS64 microprocessor
Transport/Graphics Subsystem
Peripherals
CPU
Video O ut
Audio O ut
V.90 S oft Modem
Codec
I/O