Analog Devices Inc./Maxim Integrated DS33X41+

Overview

DS33X41+ from Maxim Integrated is a single-port Ethernet-over-PDH mapping device that encapsulates IEEE 802.3 MAC frames in GFP-F, HDLC, cHDLC, or X.86 for transmission over T1/E1/J1, T3/E3, or xDSL TDM streams. It supports VCAT/LCAS link aggregation across up to 4 TDM ports, provides wire-speed bridging and traffic conditioning, and operates across -40°C to +85°C for carrier-grade access networks.

For engineers reviewing the DS33X41+ datasheet, DS33X41+ pinout, DS33X41+ application, or DS33X41+ equivalent, this page delivers verified technical context on Ethernet-to-TDM encapsulation, QoS policy enforcement, DDR SDRAM buffering, SPI/parallel microprocessor interface support, and industrial-temperature operation - all critical for EoPDH service deployment and board-level integration.

Technical Context

The DS33X41+ implements a store-and-forward architecture with dual-layer classification (VLAN/Q-in-Q/DSCP) and per-flow CIR/CBS policing for deterministic bandwidth control. Its packet processor handles GFP-F/LAPS/HDLC/cHDLC encapsulation and decapsulation with full OAM frame trapping, extraction, and insertion via μP interface.

It integrates a 10/100/1000Mbps GMII/MII/RMII MAC with autonegotiation and flow control, supports up to 200ms differential delay tolerance in VCAT/LCAS mode, and interfaces to external 125MHz DDR SDRAM for frame buffering - enabling transparent LAN extension over legacy PDH infrastructure without protocol translation.

Key Specifications

Pinout & Package

DS33X41+ is housed in a 256-ball, 17mm × 17mm CSBGA package (package code: 56-G6017-001) with 0.8mm ball pitch and exposed thermal pad. Pin functions are defined per Maxim's DS33X162/X161/X82/X81/X42/X41 pinout diagram (Figure 7-1, Rev 063008).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Ethernet-over-PDH mapping applications.

Compared with DS33X42+ and DS33X81+, the DS33X41+ delivers optimal balance of TDM port count, Ethernet interface simplicity, and thermal efficiency for single-link EoPDH edge demarcation - reducing component count and power by 30% versus dual-port or 8-port variants while retaining full GFP-F, VCAT/LCAS, and QoS feature parity.

Availability

DS33X41+ is available at Aetrix Electronics and suitable for bonded transparent LAN service, LAN extension over T1/E1, and eLINE service delivery requiring stable component supply across industrial temperature ranges and long product lifecycles.

Supply support for DS33X41+ 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) designs high-performance analog and mixed-signal ICs for communications, computing, and industrial systems - emphasizing signal integrity, power efficiency, and system-level integration.

The DS33X41+ belongs to Maxim's Ethernet-over-PDH mapping product line, engineered specifically for carrier-class TDM-to-Ethernet transport in metro access, business service gateways, and DSLAM edge cards.

FAQ

What Ethernet interface modes does the DS33X41+ support?

The DS33X41+ supports GMII, MII, and RMII Ethernet interface modes via configurable pin strapping and register settings. GMII is used for 1000Mbps operation with 8-bit wide data paths; MII supports 10/100Mbps with 4-bit data; RMII reduces pin count for 10/100Mbps with 2-bit data and shared reference clock. All modes include autonegotiation and IEEE 802.3x flow control. The DS33X41+ does not support RGMII or SGMII interfaces.

Does the DS33X41+ integrate an Ethernet PHY?

No, the DS33X41+ does not integrate an Ethernet PHY. It provides MAC-layer interfaces (GMII/MII/RMII) and requires an external PHY IC for physical layer signaling - such as the MAX24108 or compatible 10/100/1000BASE-T transceivers. This separation allows flexible PHY selection based on distance, medium (copper/fiber), and regulatory compliance requirements for the DS33X41+ design.

What external memory is required for DS33X41+ operation?

The DS33X41+ requires an external 256Mb DDR SDRAM operating at 125MHz for frame buffering, traffic shaping, and store-and-forward functionality. Maxim specifies Micron MT46V32M16 or equivalent DDR-200 compliant devices. The DS33X41+ implements full DDR timing control including DQS gating, read/write leveling, and refresh management - no external memory controller is needed.

How does DS33X41+ handle OAM frames in Ethernet-over-PDH applications?

The DS33X41+ supports OAM frame handling through dedicated μP interface registers that allow external processors to trap, extract, and insert OAM frames (e.g., IEEE 802.3ah, Y.1731) without interrupting data plane forwarding. Trapped frames are presented via the parallel or SPI interface; extracted frames are queued for host processing; inserted frames are scheduled into the transmit path with precise timing alignment. This offloads OAM processing while preserving end-to-end visibility for the DS33X41+.

Is DS33X41+ pin-compatible with other devices in the DS33X family?

The DS33X41+ shares the same 256-ball CSBGA package and pinout with DS33X162+, DS33X161+, DS33X82+, DS33X81+, and DS33X42+, as confirmed in Maxim's Figure 7-1 (Rev 063008). However, pin functionality differs across variants - for example, unused Ethernet or TDM pins on DS33X41+ may be repurposed as GPIO or clock outputs on higher-port variants. Board-level reuse requires register-level compatibility verification, not just mechanical pin matching.