DS21Q41B
DS21Q41B
Quad T1 Framer
FEATURES
• Four T1 DS1/ISDN–PRI framing transceivers
• All four framers are fully independent
• Frames to D4, ESF, and SLC–96 formats
• 8–bit parallel control port that can be connected to
either multiplexed or non–multiplexed buses
• Each of the four framers contains dual two–frame
elastic stores that can connect to asynchronous or
synchronous backplanes up to 8.192 MHz
• Extracts and inserts robbed bit signaling
• Framer and payload loopbacks
• Large counters for BPVs, LCVs, EXZs, CRC6, PCVs,
F–bit errors and the number of multiframes out of sync
• Contains ANSI ones density monitor and enforcer
• CSU loop code generator and detector
• Programmable output clocks for Fractional T1, ISDN–
PRI, Actual Size and per channel loopback applica-
tions
• Onboard FDL support circuitry
• Pin compatible with DS21Q43 Quad E1 Framer
• 5V supply; low power CMOS
• Available in 128–pin TQFP
• Industrial (–40°C to +85°C) grade version available
(DS21Q41BTN)
DESCRIPTION
The DS21Q41B combines four of the popular DS2141A
T1 Controllers onto a single monolithic die. The “B” des-
ignation denotes that some new features are available
in the Quad version that were not available in the single
T1 device. The added features in the DS21Q41B are
listed in Section 1. The DS21Q41B offers a substantial
space savings to applications that require more than
one T1 framer on a card. The Quad version is only
slightly bigger than the single T1 device. All four fram-
ers in the DS21Q41B are totally independent, they do
FUNCTIONAL DIAGRAM
RECEIVE
FRAMER
ELASTIC
STORE
TRANSMIT
FORMATTER
ELASTIC
STORE
FRAMER #0
FRAMER #1
FRAMER #2
FRAMER #3
CONTROL PORT
ACTUAL SIZE
QUAD
T1
FRAMER
not share a common framing synchronizer. Also, the
transmit and receive sides of each framer are totally
independent. The dual two–frame elastic stores con-
tained in each of the four framers can be independently
enabled and disabled as required. The DS21Q41B
meets all of the latest specifications including ANSI
T1.403 (and the emerging T1.403–199X), ANSI
T1.231–1993, AT&T TR62411, AT&T TR54016, ITU
G.704 and G.706.
ECopyright 1995 by Dallas Semiconductor Corporation.
All Rights Reserved. For important information regarding
patents and other intellectual property rights, please refer to
Dallas Semiconductor data books.
021997 1/55