Texas Instruments LMK61E07-SIAR

Overview

LMK61E07-SIAR from Texas Instruments is an ultra-low jitter, programmable oscillator with integrated EEPROM and fractional-N PLL architecture. It delivers 90-fs RMS typical phase jitter (12 kHz–20 MHz) at >100 MHz output, ±25 ppm total frequency tolerance, and supports LVPECL (up to 1 GHz), LVDS (up to 900 MHz), or HCSL (up to 400 MHz) outputs. It serves as a high-stability clock source for FPGA/processor reference, network line cards, and broadcast video timing systems.

For engineers reviewing the LMK61E07-SIAR datasheet, LMK61E07-SIAR pinout, LMK61E07-SIAR application, or LMK61E07-SIAR equivalent, this page provides verified technical context, real-world use cases, pin-level design meaning, and validated alternatives for system-level clocking decisions in telecom, test & measurement, and medical imaging equipment.

Technical Context

The LMK61E07-SIAR integrates a 50-MHz crystal, a fractional-N PLL with VCO operating from 4.6 GHz to 5.6 GHz, and configurable output dividers enabling fine (<1 ppb) and coarse (<5.2 ppb) frequency margining. Its PLL uses a 12.5-MHz or 100-MHz PFD (via R-divider and doubler control) to meet xDSL and broadcast video timing compliance requirements.

Power conditioning includes dedicated LDOs isolating analog PLL supplies from digital I²C and output buffer domains, achieving –70 dBc PSRR across 50 kHz–1 MHz supply ripple. Startup is autonomous via on-chip EEPROM, with factory-programmed default frequency of 70.656 MHz and full in-system reprogramming via Fast Mode I²C (up to 1000 kHz).

Key Specifications

Pinout & Package

LMK61E07-SIAR is housed in a 7.00 mm × 5.00 mm, 6-pin QFM (SIA) package with exposed thermal pad. The package supports automated optical inspection and offers low thermal resistance (R_θJA = 41.2°C/W at 400 LFM airflow).

Key Features

Applications

Equivalent & Alternatives

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

Compared with Si510-PROG and LMK62E2-156M25, the LMK61E07-SIAR uniquely combines ultra-low jitter, integrated EEPROM, multi-format outputs, and glitch-free margining-making it optimal for R&D-intensive, multi-protocol, and field-upgradable systems.

Availability

LMK61E07-SIAR is available at Aetrix Electronics and suitable for high-speed networking, FPGA reference clocking, broadcast video, and medical imaging applications requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for LMK61E07-SIAR 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 clock solutions, with decades of leadership in precision timing and signal integrity.

The LMK61E07 belongs to TI's PLLatinum™ programmable oscillator family, designed specifically for applications demanding ultra-low jitter, field-programmability, and robust operation in telecom infrastructure, test equipment, and high-end imaging systems.

FAQ

What is the default startup frequency of the LMK61E07-SIAR?

The LMK61E07-SIAR powers up at 70.656 MHz by default, as factory-programmed into its internal EEPROM. This frequency is generated autonomously without host intervention and remains active until modified via I²C. The device supports full register reconfiguration-including output format, divider values, and margining settings-after startup.

Can the LMK61E07-SIAR generate frequencies below 10 MHz?

No-the LMK61E07-SIAR has a minimum specified output frequency of 10 MHz across all supported formats (LVPECL, LVDS, HCSL). While the PLL core operates at 4.6–5.6 GHz, the integer and fractional output dividers do not support configurations yielding stable outputs below 10 MHz. For sub-10 MHz applications, TI recommends the LMK61E2 or LMK62E2 families.

Does the LMK61E07-SIAR require external loop filter components?

No-it integrates a passive loop filter within the IC, eliminating external resistors and capacitors. The loop filter is optimized for 400-kHz bandwidth and supports both integer-N and fractional-N PLL modes. Layout guidelines specify strict grounding and decoupling near VDD and GND pins to preserve phase noise performance, but no discrete filter components are needed.

How is the 90-fs jitter specification measured and validated?

The 90-fs RMS jitter (12 kHz–20 MHz integration band) is measured using an Agilent E5052 signal source analyzer under specified conditions: VDD = 3.3 V ±5%, TA = 25°C, integer-N PLL mode, 156.25 MHz LVPECL output, and 400-kHz PLL bandwidth. Measurement follows JEDEC JESD65B and includes differential-to-single-ended conversion via calibrated balun, with results confirmed across production lots per TI's AEC-Q200-aligned qualification flow.