Texas Instruments LMK62E0-156M25SIAT

Overview

LMK62E0-156M25SIAT from Texas Instruments is a factory-programmed, low-jitter LVPECL oscillator delivering 156.25 MHz output with ±25 ppm total frequency stability over –40°C to +85°C, 3.3-V supply, and 150 fs RMS phase jitter (12 kHz–20 MHz). It serves as a high-stability clock reference for FPGA and processor clocking in telecom infrastructure.

For engineers reviewing the LMK62E0-156M25SIAT datasheet, LMK62E0-156M25SIAT pinout, LMK62E0-156M25SIAT application, or LMK62E0-156M25SIAT equivalent, key selection criteria include LVPECL output compatibility, industrial temperature operation, PSRR of –60 dBc at 156.25 MHz, 5-mm × 3.2-mm SIA package footprint, and OE-controlled output enable/disable functionality.

Technical Context

The LMK62E0-156M25SIAT integrates a high-performance PLL-based oscillator core with internal power conditioning to achieve robust supply noise immunity. Its LVPECL output stage delivers 700–1200 mV differential swing with 260–350 ps rise/fall time and 45–55% duty cycle.

It operates exclusively from a single 3.3-V ±5% supply, features an OE input with internal pulldown and 10-kΩ recommended external pullup, and achieves startup within 10 ms after VDD reaches 3.135 V. The device uses a fixed-frequency, non-reprogrammable architecture optimized for deterministic timing performance.

Key Specifications

Pinout & Package

LMK62E0-156M25SIAT uses a 5.0 mm × 3.2 mm, 6-pin QFM (SIA) package with exposed thermal pad, pin-compatible with industry-standard 5032 XO footprints. The package supports reflow per J-STD-020 MSL Level-3 (260°C peak).

Key Features

Applications

Equivalent & Alternatives

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

Compared with LMK62E0-156M25SIAT, the LMK62E2 variant trades 25 ppm stability for lower cost, while Si5338A adds flexibility at the expense of size, complexity, and fixed-frequency simplicity.

Availability

LMK62E0-156M25SIAT is available at Aetrix Electronics and suitable for 5G infrastructure, high-speed networking, and precision test equipment requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for LMK62E0-156M25SIAT 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 leader specializing in analog, embedded processing, and clock solutions, with decades of expertise in high-performance timing devices.

The LMK62XX family is designed specifically for applications demanding ultra-low jitter, high PSRR, and industrial-grade reliability in telecom, datacenter, and test instrumentation systems.

FAQ

Is LMK62E0-156M25SIAT programmable in-system?

No. LMK62E0-156M25SIAT is factory-programmed to 156.25 MHz LVPECL output and cannot be reconfigured via I²C, SPI, or any other interface. It is a fixed-frequency oscillator intended for applications where deterministic, tamper-proof timing is required. Programming occurs during wafer probe and final test; no user-accessible configuration registers exist.

What is the recommended termination for the LVPECL outputs?

The LVPECL outputs require 150-Ω termination to VDD − 2 V (i.e., 1.3 V) on each leg (OUTP and OUTN), as specified in TI's test setup and application notes. This matches the internal 150-Ω source impedance and ensures optimal signal integrity, common-mode voltage (VDD − 1.45 V), and jitter performance. AC-coupled 50-Ω terminations are not supported.

Does the OE pin require an external pullup resistor?

Yes. The OE pin has an internal pulldown but requires a 10-kΩ external pullup to VDD to ensure reliable high-level assertion during power-up and noise immunity. Without it, OE may float near the LVCMOS threshold, causing undefined output state or increased start-up jitter. TI explicitly specifies this value in the Pin Functions table and Layout Guidelines.

Can LMK62E0-156M25SIAT operate from a 2.5-V supply?

No. LMK62E0-156M25SIAT is rated exclusively for 3.3 V ±5% (3.135 V to 3.465 V). Operation outside this range violates Absolute Maximum Ratings and may cause functional failure, increased jitter, or permanent damage. The internal regulator and output driver stages are designed for 3.3-V operation; no 2.5-V mode or voltage scaling is supported.