Analog Devices Inc./Maxim Integrated MAX3693ECJ+T

Overview

MAX3693ECJ+T from Maxim Integrated is a 4:1 parallel-to-serial serializer IC for SDH/SONET and ATM systems, converting 4-bit-wide 155.52Mbps parallel data to 622.08Mbps PECL serial output with integrated PLL clock synthesis, LVDS inputs, and operation over -40°C to +85°C in a 32-pin TQFP package.

For engineers reviewing the MAX3693ECJ+T datasheet, MAX3693ECJ+T pinout, MAX3693ECJ+T application, or MAX3693ECJ+T equivalent, key selection criteria include its 622Mbps serial rate, 155.52/77.76/51.84/38.88MHz reference clock flexibility, LVDS-to-PECL signal conversion capability, and guaranteed jitter performance (11psRMS random jitter) in telecom timing-critical designs.

Technical Context

The MAX3693ECJ+T implements a fully integrated PLL with phase/frequency detector, VCO, prescaler, and loop filter to synthesize a precise 622.08MHz internal serial clock from four selectable LVDS reference frequencies. Its 4-bit parallel input register latches data on the rising edge of PCLKI, while PCLKO provides a divided-by-4 155.52MHz LVDS clock for overhead management.

It features differential LVDS I/O buffers compliant with IEEE 1596.3, internally terminated 100Ω LVDS inputs (PD0±–PD3±, PCLKI±, RCLK±), and PECL outputs (SD±) requiring external 50Ω termination to (VCC − 2V). Timing window constraints specify 0 to +4ns PCLKO-to-PCLKI skew tolerance.

Key Specifications

Pinout & Package

MAX3693ECJ+T is housed in a 32-pin Thin Quad Flat Package (TQFP) with 0.8mm pitch, exposed pad for thermal dissipation, and lead-free (RoHS-compliant) finish indicated by the '+' suffix.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX3695ECJ+T and ICS8430M-01LFT, the MAX3693ECJ+T uniquely combines integrated 622Mbps PLL synthesis, LVDS-to-PECL conversion, and telecom-grade jitter performance in a single 32-pin TQFP-reducing component count, layout risk, and qualification effort for OC-12 line cards.

Availability

MAX3693ECJ+T is available at Aetrix Electronics and suitable for 622Mbps SDH/SONET transmission systems, ATM/SONET access nodes, and digital cross-connect equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX3693ECJ+T 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 U.S.-based semiconductor company specializing in high-performance analog, mixed-signal, and RF solutions for communications, computing, and industrial markets.

The MAX3693ECJ+T belongs to Maxim's telecom serializer product line, designed specifically for OC-12/STM-4 optical transport applications requiring low-jitter, single-supply, LVDS-to-PECL signal conversion with integrated clock synthesis.

FAQ

What reference clock frequencies does the MAX3693ECJ+T support?

The MAX3693ECJ+T supports four reference clock frequencies: 155.52MHz, 77.76MHz, 51.84MHz, and 38.88MHz. Selection is controlled by the CKSET pin voltage or resistor configuration. This allows the MAX3693ECJ+T to operate across multiple SONET/SDH hierarchy levels-including OC-3, OC-12, and OC-48-derived clocks-without changing the hardware design.

Does the MAX3693ECJ+T require external termination resistors for its LVDS inputs?

No, the MAX3693ECJ+T includes internal 100Ω differential termination for all LVDS inputs (PD0±–PD3±, PCLKI±, RCLK±), eliminating the need for external resistors. However, the LVDS parallel clock outputs (PCLKO±) require external 100Ω differential termination between pins, and the PECL serial outputs (SD±) require 50Ω termination to (VCC − 2V) or Thevenin-equivalent alternatives per the datasheet.

What is the guaranteed random jitter performance of the MAX3693ECJ+T?

The MAX3693ECJ+T guarantees 11psRMS random jitter on its 622.08Mbps PECL serial output under specified conditions (VCC = +3.3V, TA = +25°C). This value is measured and characterized-not just simulated-and meets GR-253-CORE requirements for OC-12 transmitters, ensuring reliable bit-error-rate performance in real-world optical links.

Can the MAX3693ECJ+T operate outside the -40°C to +85°C temperature range?

No-the MAX3693ECJ+T is qualified and specified only for operation from -40°C to +85°C. Electrical parameters including setup/hold time (tSU = 0ps min), supply current (ICC = 65mA max), and jitter are guaranteed only within this extended industrial temperature range. Operation beyond these limits may result in timing violations or increased BER and is not supported by Maxim's reliability testing.

How is the PCLKO output used in system-level timing architecture?

The PCLKO output of the MAX3693ECJ+T is a 155.52MHz LVDS clock derived by dividing the internal 622.08MHz serial clock by four. It is intended to clock overhead management circuitry (e.g., section/path overhead processors) and must be used with 100Ω differential termination. Its timing relationship to PCLKI is tightly controlled (0 to +4ns skew), enabling deterministic alignment of payload and overhead insertion.