Analog Devices Inc./Maxim Integrated DS2143Q

Overview

DS2143Q from Maxim Integrated (formerly Dallas Semiconductor) is an E1 framing transceiver IC designed as a software-configurable slave/coprocesor for microcontroller-based telecom line cards. It performs full E1 frame alignment, CAS/CCS signaling extraction and insertion, CRC4 error detection/generation, HDB3 encoding/decoding, and supports fractional E1 drop-and-insert applications with programmable output clocks. It operates at 5 V and consumes 50 mW.

For engineers reviewing the DS2143Q datasheet, DS2143Q pinout, DS2143Q application, or DS2143Q equivalent, this page delivers verified technical context, exact pin functions per PLCC-44 package, confirmed E1 protocol compliance (G.704/G.706/G.732), elastic store behavior, alarm handling logic, and two validated alternative E1 framers for ISDN-PRI and carrier-grade access systems.

Technical Context

The DS2143Q implements a fully independent receive and transmit path with dual-frame elastic store buffering, enabling slip compensation during clock domain transitions. Its parallel control port supports both Intel and Motorola bus timing via BTS pin configuration, and it features 69 internal 8-bit registers for real-time configuration of framing format (CAS/CCS/CRC4), Sa/Si bit handling, and alarm masking.

It integrates dedicated circuitry for FAS/CRC4 multiframe synchronization, E-bit generation/counting, BPV monitoring, and local loopback (LLB) mode for system-level diagnostics. The device extracts and inserts CAS bits in timeslot 16, supports G.802 E1-to-T1 mapping, and provides programmable TCHCLK/RCHCLK (256 kHz), TLCLK/RLCLK (4–20 kHz), and frame-sync outputs.

Key Specifications

Pinout & Package

DS2143Q is supplied in a 44-pin Plastic Leaded Chip Carrier (PLCC) package, 16.5 mm × 16.5 mm body, 1.7 mm height, J-lead profile. Pin 1 marked by corner notch; pin numbering follows standard PLCC CCW sequence starting at notch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with DS2143Q, DS2155 offers integrated line drive at the cost of layout inflexibility and higher power, while MC145508 provides minimal E1 framing at the expense of protocol adaptability and diagnostic capability-making DS2143Q the optimal balance for programmable, carrier-grade E1 edge nodes.

Availability

DS2143Q is available at Aetrix Electronics and suitable for ISDN-PRI gateways, E1 line cards for PBX systems, and fractional E1 drop-and-insert nodes requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for DS2143Q 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 (acquired by Analog Devices in 2021) designs precision analog and mixed-signal ICs for communications, computing, and industrial applications, with deep heritage in telecom timing and interface solutions.

The DS2143Q belongs to Maxim's legacy E1/T1 framer product line, engineered specifically for carrier-class access equipment requiring software-defined framing, robust alarm handling, and interoperability with global E1 standards.

FAQ

What is the primary function of the DS2143Q in an E1 system?

The DS2143Q serves as a comprehensive E1 framing transceiver that performs frame alignment, CAS/CCS signaling extraction and insertion, CRC4 error detection/generation, HDB3 encoding/decoding, and elastic store buffering. It operates as a coprocessor to a host microcontroller, offloading time-critical E1 physical layer tasks while maintaining full software configurability for evolving network requirements.

Does the DS2143Q support both CAS and CCS signaling modes?

Yes, the DS2143Q supports both Channel Associated Signaling (CAS) and Common Channel Signaling (CCS) modes via the RSM bit (CCR.3). In CAS mode, it extracts and inserts signaling bits in timeslot 16; in CCS mode, it handles Si and Sa bits across the multiframe structure. Configuration is performed through the Common Control Register at address 14h.

How does the elastic store in the DS2143Q handle clock domain mismatches?

The DS2143Q implements a two-frame elastic store that compensates for timing differences between RCLK and TCLK domains. When enabled (RCR2.1 = 1), it repeats or deletes frames to maintain data continuity, signaling slips via the SLIP bit in Status Register 1. The store requires SYSCLK (1.544 or 2.048 MHz) and supports automatic E-bit generation during slips.

Can the DS2143Q operate with Intel- and Motorola-style microprocessor buses?

Yes, the DS2143Q supports both bus architectures via the BTS pin (Pin 14). When BTS = 0, it uses Intel timing (RD/WR active-low strobes); when BTS = 1, it uses Motorola timing (DS/R/W active-low strobes). Address/data multiplexing is handled internally, and register access timing is defined in the AC Electrical Characteristics section of the datasheet.

What alarm conditions does the DS2143Q detect and report?

The DS2143Q detects and reports 16 distinct alarms including Receive Loss of Sync (RLOS), Loss of Transmit Clock (LOTC), Remote Alarm (RRA), Carrier Loss (RCL), CAS Multiframe loss (CASRC), Elastic Store Slip (SLIP), Bipolar Violations (BPV), and CRC4 errors (E-bit). Alarms are latched in Status Registers 1 and 2 and can be individually masked via IMR1/IMR2 to control INT1/INT2 assertion.