Analog Devices Inc./Maxim Integrated DS4266P+

Overview

DS4266P+ from Maxim Integrated is a 266MHz LVPECL-output DDR clock oscillator in a 5mm × 3.2mm × 1.49mm 10-lead LCCC ceramic package, designed as a low-jitter (≤0.7psRMS, 12kHz–20MHz), tight-duty-cycle (48%/52%), ±50ppm-stable timing source for high-speed DDR memory subsystems.

For engineers reviewing the DS4266P+ datasheet, DS4266P+ pinout, DS4266P+ application, or DS4266P+ equivalent, key selection criteria include LVPECL output compatibility, 3.3V supply operation, OE-controlled three-state functionality, thermal performance (θ_JA = 90°C/W), and RoHS-compliant Au/Ni lead finish.

Technical Context

The DS4266P+ integrates a fundamental-mode quartz crystal with a SiGe-based PLL synthesizer to generate a precise 266MHz differential clock. Its architecture delivers single-sideband phase noise of –113dBc/Hz at 1kHz offset and –153dBc/Hz at 20MHz offset, meeting stringent DDR2/DDR3 clock integrity requirements.

It supports active-high output enable (OE) with internal 100kΩ pull-up, enabling fast output disable (t_PAZ ≤ 200ns) and re-enable (t_PZA ≤ 200ns). Output termination requires dual 50Ω resistors to PECL_BIAS (V_CC – 2.0V), and the exposed paddle (EP) must remain unconnected.

Key Specifications

Pinout & Package

DS4266P+ is housed in a hermetically sealed 10-lead LCCC ceramic package (5.00mm × 3.20mm × 1.49mm) with an unconnected exposed paddle (EP). Pin 1 is OE; pins 2,7–10 are no-connect; pin 3 is GND; pin 4 is OUTP; pin 5 is OUTN; pin 6 is VCC.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar DDR clock oscillator applications.

Compared with DS4266D+ and Si53302-A01AGM, DS4266P+ delivers the lowest jitter and tightest duty cycle for fixed-frequency DDR2/DDR3 clocking, but lacks programmability and operates exclusively at 3.3V with mandatory PECL_BIAS implementation.

Availability

DS4266P+ is available at Aetrix Electronics and suitable for DDR2 memory modules, DDR3 server DIMMs, network switch ASIC clocking, and industrial FPGA-based memory interfaces requiring stable component supply, guaranteed RoHS compliance, and long-lifecycle availability.

Supply support for DS4266P+ 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 precision analog, mixed-signal, and high-frequency timing solutions for industrial, communications, and computing markets.

The DS4-XO family-including DS4266P+-was engineered specifically for DDR memory clocking, emphasizing low jitter, tight duty cycle, and robust differential output drive in miniature ceramic packages.

FAQ

What output type does the DS4266P+ provide, and how is it terminated?

The DS4266P+ provides LVPECL output. It requires dual 50Ω terminations-one from OUTP to PECL_BIAS (V_CC – 2.0V), and one from OUTN to the same PECL_BIAS node. This configuration establishes the correct common-mode voltage and differential swing. Unlike LVDS, DS4266P+ does not use 100Ω across OUTP/OUTN. Proper PECL_BIAS generation is critical for DS4266P+ functionality and signal integrity.

Does the DS4266P+ support output enable/disable, and what is its behavior when disabled?

Yes, DS4266P+ features an active-high Output Enable (OE) pin with internal 100kΩ pull-up. When OE is driven low, DS4266P+ places both OUTP and OUTN into high-impedance state relative to PECL_BIAS, effectively disabling the output without short-circuit risk. Propagation delay from OE low to high-Z is ≤200ns. This allows dynamic clock gating in power-sensitive DDR systems without external switches.

What is the frequency stability specification of the DS4266P+, and what factors does it include?

The DS4266P+ guarantees ±50ppm total frequency stability over temperature (–40°C to +85°C), supply voltage (±5% of 3.3V), load variation (±10% termination), initial tolerance (±20ppm), and 15-year aging (±7ppm). This comprehensive specification means DS4266P+ maintains timing accuracy across full operational life and environmental stress without calibration-critical for unattended DDR memory systems.

Can the DS4266P+ be used in place of the DS4266D+, and what design changes are required?

No, DS4266P+ cannot be directly substituted for DS4266D+ without board-level modifications. DS4266P+ requires LVPECL termination (dual 50Ω to PECL_BIAS), while DS4266D+ uses LVDS termination (100Ω across OUTP/OUTN). Swapping them demands changes to termination resistors, bias network, and possibly routing. DS4266P+ also draws higher current (up to 100mA vs. 75mA), affecting power delivery design. Always verify receiver compatibility before substitution.

What package and thermal characteristics define the DS4266P+ for PCB layout?

DS4266P+ uses a 5.00mm × 3.20mm × 1.49mm 10-lead LCCC ceramic package with unconnected exposed paddle (EP). Its thermal resistance is θ_JA = 90°C/W. For optimal thermal performance, the DS4266P+ footprint must avoid solder mask over the EP area and use minimal thermal vias to inner ground planes-never connect EP electrically. The N.C. pins (2,7–10) must remain unconnected and unstubbed in layout.