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REV: 040804
Note:
may be simultaneously available through various sales channels. For information about device errata, click here: www.maxim-ic.com/errata
.
GENERAL DESCRIPTION
The DS21455 and DS21458 are quad monolithic
devices featuring independent transceivers that
can be software configured for T1, E1, or J1
operation. Each is composed of a line interface
unit (LIU), framer, HDLC controllers, and a
TDM backplane interface, and is controlled via
an 8-bit parallel port configured for Intel or
Motorola bus operations. The DS21455* is a
direct replacement for the older DS21Q55 quad
MCM device. The DS21458, in a smaller
package (17mm CSBGA) and featuring an
improved controller interface, is software
compatible with the older DS21Q55.
*
The JTAG function on the DS21455/DS21458 is a single
controller for all four transceivers, unlike the DS21Q55, which has
a JTAG controller-per-transceiver architecture.
APPLICATIONS
Routers
Channel Service Units (CSUs)
Data Service Units (DSUs)
Muxes
Switches
Channel Banks
T1/E1 Test Equipment
ORDERING INFORMATION
PART
TEMP RANGE
PIN-PACKAGE
DS21455
0°C to +70°C
256 BGA
(27mm x 27mm)
256 BGA
(27mm x 27mm)
256 CSBGA
(17mm x 17mm)
256 CSBGA
(17mm x 17mm)
DS21455N
-40°C to +85°C
DS21458
0°C to +70°C
DS21458N
-40°C to +85°C
FEATURES
Four Independent Transceivers, Each Having
the Following Features:
Complete T1 (DS1)/ISDN-PRI/J1
Transceiver Functionality
Complete E1 (CEPT) PCM-30/ISDN-
PRI Transceiver Functionality
Short- and Long-Haul Line Interface for
Clock/Data Recovery and Waveshaping
CMI Coder/Decoder
Crystal-Less Jitter Attenuator
Fully Independent Transmit and Receive
Functionality
Dual HDLC Controllers
On-Chip Programmable BERT Generator
and Detector
Internal Software-Selectable Receive-
and Transmit-Side Termination Resistors
for 75
/100
/120
T1 and E1
Interfaces
Dual Two-Frame Elastic-Store Slip
Buffers that can Connect to
Asynchronous Backplanes Up to
16.384MHz
16.384MHz, 8.192MHz, 4.096MHz, or
2.048MHz Clock Output Synthesized to
Recovered Network Clock
Programmable Output Clocks for
Fractional T1, E1, H0, and H12
Applications
Interleaving PCM Bus Operation
8-Bit Parallel Control Port, Multiplexed
or Nonmultiplexed, Intel or Motorola
IEEE 1149.1 JTAG-Boundary Scan
3.3V Supply with 5V Tolerant Inputs and
Outputs
DS21455 Directly Replaces DS21Q55
Signaling System 7 (SS7) Support
RAI-CI, AIS-CI Support
DS21455/DS21458
Quad T1/E1/J1 Transceivers
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