Texas Instruments LMK61E2-100M00SIAR

Overview

LMK61E2-100M00SIAR from Texas Instruments is an ultra-low-jitter LVPECL-output oscillator generating a precise 100 MHz reference clock for high-speed digital systems. It delivers 90 fs RMS jitter (typical), ±50 ppm total frequency tolerance, and operates from a single 3.3 V supply across –40°C to +85°C. Its primary role is timing reference generation in FPGA/ASIC clock trees requiring sub-100-fs jitter performance.

For engineers reviewing the LMK61E2-100M00SIAR datasheet, LMK61E2-100M00SIAR pinout, LMK61E2-100M00SIAR application, or LMK61E2-100M00SIAR equivalent, key selection criteria include differential LVPECL output capability up to 1 GHz, robust PSRR (–70 dBc), 6-pin QFM package compatibility with industry-standard 7050 footprints, and factory-programmed fixed-frequency operation without external configuration.

Technical Context

The LMK61E2-100M00SIAR integrates a high-stability PLL-based oscillator core with internal power conditioning to suppress supply noise. Its LVPECL output stage supports 100 MHz at 700–1200 mV differential swing with 120–200 ps rise/fall time and 45–55% duty cycle.

It features an LVCMOS OE input with internal pull-up, enabling output disable into high-impedance state within 50 µs. The device achieves 90 fs RMS phase jitter (12 kHz–20 MHz integration band) at 100 MHz output and maintains –165 dBc/Hz phase noise floor beyond 10 MHz offset.

Key Specifications

Pinout & Package

LMK61E2-100M00SIAR uses a 6-pin QFM (SIA) package measuring 7.0 mm × 5.0 mm with exposed thermal pad. Pin 1 is marked by dot; top-view orientation follows standard IC convention.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-jitter oscillator applications.

Compared with LMK61E2-100M00SIAR, the SIAT variant offers identical timing performance in tape-and-reel format for production lines, while the Si510 provides superior ±20 ppm stability and LVDS output - suitable when system-level noise immunity favors LVDS over LVPECL and tighter long-term accuracy is prioritized over raw jitter minimization.

Availability

LMK61E2-100M00SIAR is available at Aetrix Electronics and suitable for FPGA clock distribution, 10G Ethernet line cards, and medical imaging data acquisition requiring stable component supply, consistent parametric performance, and long-term manufacturing continuity.

Supply support for LMK61E2-100M00SIAR 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

Texas Instruments is a global semiconductor company specializing in analog, embedded processing, and high-performance timing solutions for industrial, automotive, and communications markets.

The LMK61XX family was designed to replace quartz-based oscillators with silicon-based alternatives offering superior jitter performance, supply noise immunity, and integration - targeting high-speed digital infrastructure demanding sub-100-fs timing precision.

FAQ

What output format does the LMK61E2-100M00SIAR support?

The LMK61E2-100M00SIAR supports LVPECL output only - it is factory-programmed for 100 MHz LVPECL operation with 700–1200 mV differential swing. Unlike some variants in the LMK61XX family, it does not support LVDS or HCSL output formats; its pinout and internal configuration are fixed for LVPECL.

Does the LMK61E2-100M00SIAR require external configuration or programming?

No, the LMK61E2-100M00SIAR is a factory-programmed oscillator - all timing parameters, output format, and frequency are set during manufacturing. It requires no I²C, SPI, or other configuration interface; only power, ground, and OE control are needed for operation.

What is the recommended power supply bypassing for the LMK61E2-100M00SIAR?

Texas Instruments specifies a three-capacitor bypass network for the LMK61E2-100M00SIAR: 10 µF (bulk), 1 µF (mid-frequency), and 0.1 µF (high-frequency), all placed as close as possible to the VDD pin. Capacitors should be mounted on the component side using 0201 or 0402 packages to minimize inductance and ensure optimal PSRR performance.

How does the OE pin function on the LMK61E2-100M00SIAR?

The OE (Output Enable) pin on the LMK61E2-100M00SIAR is an LVCMOS input with internal pull-up. When held high (≥1.4 V), outputs are active; when pulled low (≤0.6 V), both OUTP and OUTN enter high-impedance state within 50 µs. This enables dynamic clock gating without affecting internal oscillator operation.

Is the LMK61E2-100M00SIAR pin-compatible with standard 7050 crystal oscillator footprints?

Yes, the LMK61E2-100M00SIAR uses a 6-pin QFM package measuring 7.0 mm × 5.0 mm - identical in outline and pin spacing to industry-standard 7050 XO packages. Its pin 1 location and terminal assignments (OE, NC, GND, OUTN, OUTP, VDD) match common 7050 footprint layouts, enabling mechanical and electrical drop-in replacement.