Analog Devices Inc./Maxim Integrated DS2182QN

Overview

DS2182QN from Maxim Integrated is a T1 line monitor IC designed for real-time performance monitoring of T1 digital telecommunication lines. It performs framing synchronization (Superframe and Extended Superframe), counts four distinct error types (16-bit bipolar violation, 8-bit CRC, 8-bit OOF, 8-bit frame bit error), and delivers alarm outputs including RLOS, RYEL, RBV, and RFER. It operates at -40°C to +85°C in 28-pin PLCC packaging and supports 1.544MHz receive clock input.

For engineers reviewing the DS2182QN datasheet, DS2182QN pinout, DS2182QN application, or DS2182QN equivalent, key selection considerations include its dual-framing mode support (193S/193E), on-chip burst-mode serial interface for fast status polling, auto-counter reset capability, B8ZS codeword detection, and carrier loss detection via 192-zero-string monitoring.

Technical Context

The DS2182QN implements a hardware-based receive synchronizer that detects loss-of-frame/multiframe alignment and performs off-line resync using configurable criteria (RCR1.3/RCR1.2). It supports two framing modes-12-frame Superframe (193S) and 24-frame Extended Superframe (193E)-with independent sync algorithms, CRC6 validation, and S-bit/FDL-based yellow alarm detection.

Its serial port uses an 8-bit address/command byte (ACB) with LSB-first data transfer, burst-mode capability (ACB.7), and asynchronous operation relative to RCLK. All four error counters are presettable, saturate at defined thresholds (65,535 for BVCR, 255 for others), and generate latched status bits (RSR1/RSR2) with maskable interrupts via RIMR1/RIMR2.

Key Specifications

Pinout & Package

DS2182QN is housed in a 28-pin PLCC package with gull-wing leads, optimized for thermal dissipation and board-level reliability in telecom line cards. Pin numbering follows standard PLCC top-view convention (pin 1 at index corner).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar T1 line monitoring applications.

Compared with DS2182N and DS2182Q, the DS2182QN uniquely combines PLCC packaging for automated assembly with -40°C to +85°C qualification-making it the sole option for ruggedized, volume-manufactured T1 line cards requiring both surface-mount compatibility and industrial temperature resilience.

Availability

DS2182QN is available at Aetrix Electronics and suitable for T1 channel bank monitoring, telecom line card diagnostics, remote DSLAM supervision, and T1 network management gateways requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for DS2182QN 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 precision analog, mixed-signal, and high-reliability interface solutions for communications, industrial, and automotive markets.

The DS2182QN belongs to Maxim's T1/E1 line interface and monitoring product line, engineered specifically for ANSI T1.231-compliant telecom infrastructure where deterministic framing, low-latency alarm reporting, and multi-decade field reliability are mandatory.

FAQ

What framing standards does the DS2182QN support?

The DS2182QN supports both ANSI T1.403 Superframe (193S, 12-frame) and Extended Superframe (193E, 24-frame) formats. Frame mode selection is controlled by the FM bit (RCR2.4): logic 0 selects 193S, logic 1 selects 193E. The DS2182QN meets ANSI T1.231 requirements for T1 line monitoring in either mode, with independent sync algorithms, CRC6 validation in 193E, and S-bit/FDL-based yellow alarm detection.

How does the DS2182QN handle carrier loss detection?

The DS2182QN detects carrier loss (RCL) by monitoring for 192 consecutive zero bits at the RPOS/RNEG inputs. When detected, the RCL output goes high and the RCL bit (RSR1.5) is latched. Recovery occurs upon receiving ≥14 ones within 112 bit positions, causing RCL to go low. This behavior is fully hardware-implemented and independent of framing mode or sync status-ensuring reliable fail-safe signaling even during loss-of-sync conditions.

Can the DS2182QN count excessive zero strings, and how is this configured?

Yes, the DS2182QN can count excessive zero strings when the BVCRF bit (RCR2.5) is set to 1. In B8ZS-enabled mode (B8ZS=1), it counts occurrences of eight consecutive zeros; in B8ZS-disabled mode (B8ZS=0), it counts 16-zero strings. This function is implemented in the same 16-bit BVCR used for bipolar violations, sharing saturation and interrupt behavior (BPVCS flag in RSR2.0), enabling unified error threshold management without additional registers.

What is the purpose of the burst mode feature in the DS2182QN serial interface?

The burst mode in the DS2182QN serial interface allows consecutive read or write operations across all 11 internal registers using a single CS assertion. Enabled by setting ACB.7 and addressing register 0000, it reduces host processor overhead during system initialization or status polling. Critically, when RCR1.4 is set, burst reads automatically reset all four error counters-ensuring atomic status capture and eliminating race conditions between counter increment and readback in high-error-rate environments.

Does the DS2182QN require external components for basic T1 monitoring operation?

No, the DS2182QN operates autonomously with only a 5V supply (VDD/VSS), the incoming T1 differential signal applied to RPOS/RNEG, and a 1.544MHz receive clock (RCLK) derived from the line. All framing, error counting, alarm generation, and serial interface logic are integrated. External pull-up resistors are required only for open-drain outputs (INT, RYEL, RLOS) and optional for SDI/SDO in bidirectional configurations-no external timing crystals, PLLs, or support ICs are needed.