Analog Devices Inc./Maxim Integrated DS21354LN+

Overview

DS21354LN+ from Maxim Integrated is a 3.3V single-chip E1 transceiver (SCT) implementing full CEPT PCM-30/ISDN-PRI line interface functionality, with on-board clock/data recovery from AMI/HDB3 waveforms, 32-bit or 128-bit crystal-less jitter attenuation, dual elastic store buffers, and IEEE 1149.1 JTAG boundary scan - designed for telecom access equipment operating over 0–2km twisted-pair cables at -40°C to +85°C.

For engineers reviewing the DS21354LN+ datasheet, DS21354LN+ pinout, DS21354LN+ application, or DS21354LN+ equivalent, this page delivers verified technical context, exact pin roles, real-world E1 framer and HDLC controller use cases, and validated alternative parts for carrier-grade timing and signaling systems requiring G.703/G.704/G.823 compliance.

Technical Context

The DS21354LN+ integrates independent transmit and receive paths with fully decoupled framer/formatter and line interface blocks, enabling direct monitoring of bipolar data streams and support for optical/HDSL NRZ interfaces. It supports FAS, CAS, CCS, and CRC4 framing formats and provides hardware-based signaling reinsertion synchronized to backplane multiframe clocks.

Its 8.192MHz clock synthesizer eliminates external crystals, while the dual two-frame elastic stores accept asynchronous backplane clocks up to 8.192MHz and enable interleave bus operation in byte or frame mode. The HDLC controller handles Sa-bit links or DS0/sub-DS0 channels using 64-byte buffers with full register-level control.

Key Specifications

Pinout & Package

DS21354LN+ is housed in a 100-pin LQFP package (14mm × 14mm, 0.5mm pitch), thermally optimized for telecom line card PCB layouts with integrated ground plane coupling.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar E1 transceiver applications.

Compared with DS21554LN+ and XR22061ILF, the DS21354LN+ uniquely combines 3.3V operation, crystal-less jitter attenuation, IEEE 1149.1 testability, and 8.192MHz clock synthesis - making it optimal for new-generation compact, low-power, and test-ready E1 line cards.

Availability

DS21354LN+ is available at Aetrix Electronics and suitable for ISDN-PRI gateways, DSLAM line cards, remote alarm monitors, and field-deployable E1 testers requiring stable component supply across extended temperature ranges and long lifecycle commitments.

Supply support for DS21354LN+ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Maxim Integrated (now part of Analog Devices) is a semiconductor company specializing in high-performance analog, mixed-signal, and RF solutions for communications, computing, and industrial markets.

The DS21354LN+ belongs to Maxim's Single-Chip Transceiver (SCT) product line, engineered specifically for carrier-class E1 line interface applications demanding full G.703/G.704 compliance, autonomous alarm handling, and seamless integration into asynchronous backplane architectures.

FAQ

What is the primary function of the DS21354LN+ in an E1 system?

The DS21354LN+ serves as a complete E1 single-chip transceiver, performing clock and data recovery from AMI/HDB3 line signals, E1 framing (FAS/CRC4/CAS), signaling extraction/insertion (Sa/Si/CAS), jitter attenuation, and HDLC-controlled channel transport. It replaces discrete framer, line interface, and clock recovery ICs in telecom access equipment, enabling compact, low-power E1 line cards with full ITU-T and ETSI standard compliance.

Does the DS21354LN+ require an external crystal for jitter attenuation?

No, the DS21354LN+ features a crystal-less jitter attenuator that operates using its internal 8.192MHz clock synthesizer - eliminating the need for an external 32.768MHz crystal. This reduces bill-of-materials cost and PCB area while maintaining full G.823 jitter transfer and generation compliance for both transmit and receive paths.

How does the DS21354LN+ handle E1 cable length variation from 0 to over 2km?

The DS21354LN+ automatically adjusts line build-out via internal programmable gain and equalization on the RRING/RTIP receive inputs, achieving usable sensitivity from 0 dB to -43 dB. This adaptive response compensates for nonlinear losses across 22AWG twisted-pair cables up to 2km, ensuring robust clock/data recovery without manual calibration or external components.

Can the DS21354LN+ operate with both Intel- and Motorola-style parallel buses?

Yes, the DS21354LN+ supports both multiplexed and nonmultiplexed 8-bit parallel control ports with selectable timing modes (BTS = 0/1, MUX = 0/1), enabling direct interface to Intel 8080-style or Motorola 68000-style microcontrollers without glue logic. Register access timing is fully documented for both bus types across all operating voltages and temperatures.

What alarm conditions does the DS21354LN+ detect and generate autonomously?

The DS21354LN+ autonomously detects RLOS (Receive Loss of Signal), RCL (Receive Carrier Loss), RRA (Remote Alarm Indication), and RAIS (Remote AIS), and generates AIS (Alarm Indication Signal) and RAI (Remote Alarm Indication) per ETS 300 011 specifications. All alarms trigger interrupt-capable status bits and feed large on-chip counters for BPV, CRC4, E-bit, and FAS errors - enabling real-time network health monitoring without host CPU polling.