Analog Devices Inc./Maxim Integrated DS33Z11

Overview

DS33Z11 from Maxim Integrated is a 10/100 Ethernet-to-TDM mapper IC that encapsulates IEEE 802.3 MAC frames into HDLC or X.86 (LAPS) for transport over synchronous PDH/TDM links up to 52Mbps. It features MII/RMII Ethernet interfaces, a 52Mbps bidirectional TDM serial port, CIR bandwidth control in 512kbps increments, external SDRAM buffering, and hardware/SPI standalone operation mode. It enables transparent LAN extension over T1/E1/J1, T3/E3, OC-1, or DSL physical layers.

For engineers reviewing the DS33Z11 datasheet, DS33Z11 pinout, DS33Z11 application, or DS33Z11 equivalent, key selection considerations include its 169-ball CSBGA package, dual Ethernet interface support (MII and RMII), programmable HDLC/X.86 framing, fractional CIR controller, and JTAG-compliant test infrastructure - all critical for carrier-grade TDM-over-Ethernet gateway design.

Technical Context

The DS33Z11 implements a store-and-forward packet engine with full wire-speed throughput at 10/100Mbps Ethernet rates and 52Mbps TDM line rates. Its architecture integrates independent transmit/receive timing domains for the TDM serial port, enabling synchronization to external network clocks (e.g., T1/E1 line timing) while maintaining Ethernet MAC timing integrity.

It supports three operational modes: microprocessor-controlled (via parallel bus or SPI), hardware-configured (using dedicated mode pins), and EEPROM-booted configuration. The built-in BERT engine provides PRBS pattern generation and monitoring on the TDM interface, and IEEE 1149.1 JTAG enables boundary-scan testing and debug access to internal registers and I/O states.

Key Specifications

Pinout & Package

DS33Z11 is housed in a 14mm × 14mm, 169-ball Chip-Scale Ball Grid Array (CSBGA) package (package code: 56-G6035-001), optimized for high-density telecom line-card layouts and thermal performance in industrial temperature range (–40°C to +85°C).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Ethernet-to-TDM mapping applications.

Compared with DS33ZH11 and PMC4511, the DS33Z11 uniquely combines full microprocessor bus support, external SDRAM buffering, multi-protocol framing (HDLC/X.86), and fine-grained CIR control - making it the only option among the three suitable for flexible, high-capacity, carrier-grade Ethernet pseudowire gateways.

Availability

DS33Z11 is available at Aetrix Electronics and suitable for transparent LAN extension, Ethernet-over-T1/E1 service delivery, and DSL-based business Ethernet access requiring stable component supply across industrial temperature ranges and long product lifecycles.

Supply support for DS33Z11 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 DS33Z11 belongs to Maxim's Ethernet-to-TDM mapper product line, designed specifically for carrier-class Ethernet pseudowire edge devices that bridge LANs to legacy TDM infrastructure including T1/E1, T3/E3, OC-1, and DSL physical layers.

FAQ

What is the primary function of the DS33Z11?

The DS33Z11 is a dedicated Ethernet-to-TDM mapper IC that converts IEEE 802.3 MAC frames into HDLC or X.86 (LAPS) encapsulated payloads for transport over synchronous TDM networks. It performs store-and-forward packet processing at wire speed, supports 10/100Mbps Ethernet and up to 52Mbps TDM line rates, and enables transparent LAN extension across legacy telecom infrastructure. The DS33Z11 is not a general-purpose switch or router but a purpose-built layer-2 bridging element for pseudowire applications.

Does the DS33Z11 require an external processor to operate?

No - the DS33Z11 supports three distinct operational modes: microprocessor-controlled (via parallel bus or SPI), hardware-configured (using dedicated MODEC/HWMODE pins), and EEPROM-booted configuration. In hardware mode, the DS33Z11 boots autonomously with preloaded settings and operates without any host processor intervention. This makes the DS33Z11 suitable for fanless, low-power, or firmware-free CPE deployments where reliability and boot-time determinism are critical.

What types of TDM physical layers does the DS33Z11 support?

The DS33Z11 supports bidirectional synchronous TDM interconnect up to 52Mbps over xDSL, T1/E1/J1, T3/E3, V.35/Optical, OC-1/EC-1, and SONET/SDH tributary interfaces. Its 52Mbps serial port accommodates the full range of common telecom line rates - including 1.544Mbps (T1), 2.048Mbps (E1), 34.368Mbps (E3), 44.736Mbps (T3), and 51.84Mbps (OC-1) - with independent transmit/receive timing to lock to external network clocks.

How does the Committed Information Rate (CIR) controller work in the DS33Z11?

The DS33Z11's CIR controller allocates fractional bandwidth from 512kbps up to the full TDM line rate in precise 512kbps increments. It operates in the WAN transmit path to enforce bandwidth limits per virtual circuit or service flow, enabling SLA-compliant Ethernet pseudowire provisioning. The CIR value is programmable via register writes or hardware-mode configuration pins, and it directly shapes traffic before HDLC/X.86 encapsulation - ensuring deterministic bandwidth delivery without packet drops or jitter.

What is the role of external SDRAM in DS33Z11-based systems?

The DS33Z11 requires an external 16MB, 100MHz SDRAM to provide deep packet buffering for jitter tolerance, burst absorption, and store-and-forward operation. This external memory enables seamless handling of Ethernet frame bursts and TDM timing mismatches - especially critical in asymmetric or variable-delay environments like DSL or optical links. Without the SDRAM, the DS33Z11 cannot perform full wire-speed forwarding or maintain frame integrity under network stress conditions.