Texas Instruments LMK6CE15625DDLFT

Overview

LMK6CE15625DDLFT from Texas Instruments is a fixed-frequency, ultra-low-jitter BAW-based LVCMOS oscillator delivering 156.25 MHz output at 1.8 V supply, operating across –40°C to +105°C, with ±25 ppm total frequency stability and integrated LDO for supply noise immunity - deployed as a reference clock in high-speed SERDES, PCIe Gen 7, and optical transport systems.

For engineers reviewing the LMK6CE15625DDLFT datasheet, LMK6CE15625DDLFT pinout, LMK6CE15625DDLFT application, or LMK6CE15625DDLFT equivalent, key selection criteria include its 156.25 MHz LVCMOS output, 2.5 mm × 2.0 mm DLF package, sub-500 fs RMS jitter at 100 MHz (12 kHz–20 MHz), extended industrial temperature range, and Output Enable (Pin 1, active-high) functionality.

Technical Context

The LMK6CE15625DDLFT integrates a Bulk-Acoustic Wave (BAW) resonator directly into its silicon package, eliminating external crystal dependencies and enabling factory-programmed fixed-frequency operation. Its fractional output divider supports precise 156.25 MHz generation without external PLL components.

It features an integrated LDO delivering –72 dBc PSRR at 500 kHz ripple, start-up time < 5 ms, and Output Enable (OE) control on Pin 1. The device operates exclusively in LVCMOS mode within the LMK6C variant family, with no differential output capability.

Key Specifications

Pinout & Package

LMK6CE15625DDLFT uses a 4-pin VSON (DLF-4) package measuring 2.5 mm × 2.0 mm, optimized for space-constrained PCB layouts in high-density networking and telecom modules.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LMK6CE15625DDEFT, the LMK6CE15625DDLFT offers superior space efficiency and marginally better thermal performance in compact layouts; versus Si510-156M250, it delivers robust supply noise immunity and smaller footprint but requires no external filtering or regulator design effort.

Availability

LMK6CE15625DDLFT is available at Aetrix Electronics and suitable for 100G/400G optical transport, PCIe Gen 7 server platforms, and industrial baseband units requiring stable component supply, long-lifecycle support, and guaranteed traceable sourcing.

Supply support for LMK6CE15625DDLFT 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 vertically integrated manufacturing and design expertise in precision timing.

The LMK6C product line delivers factory-programmed, BAW-based oscillators targeting high-speed serial interface reference clocks - engineered for PCIe, Ethernet, optical networking, and industrial applications demanding ultra-low jitter and extended temperature reliability.

FAQ

What is the output type and drive capability of the LMK6CE15625DDLFT?

The LMK6CE15625DDLFT provides a single-ended LVCMOS output with typical VOH = 1.44 V and VOL = 0.36 V at 1.8 V supply and 3.6 mA load. Its output impedance is 40–60 Ω, supporting capacitive loads up to 15 pF at frequencies above 50 MHz - making it compatible with standard FPGA and ASIC clock inputs without external termination.

Does the LMK6CE15625DDLFT support frequency adjustment or reprogramming?

No, the LMK6CE15625DDLFT is a factory-programmed fixed-frequency oscillator. It delivers exactly 156.25 MHz and cannot be tuned, reconfigured, or updated in-system. All parameters - frequency, output type (LVCMOS), voltage (1.8 V), temperature grade (–40°C to +105°C), and function pin assignment (Pin 1 = OE) - are set during manufacturing and are immutable.

How does the integrated LDO in the LMK6CE15625DDLFT improve system-level timing performance?

The integrated LDO in the LMK6CE15625DDLFT achieves –72 dBc PSRR at 500 kHz, suppressing supply-induced spurs and jitter. This allows direct connection to noisy digital power rails without external regulators or ferrite beads - reducing component count while maintaining ≤500 fs RMS jitter (12 kHz–20 MHz) even under ripple conditions that would degrade conventional oscillators.

What is the start-up time and Output Enable latency for the LMK6CE15625DDLFT?

The LMK6CE15625DDLFT has a start-up time of <5 ms from 0.95×VDD to fully stable output. Its Output Enable (Pin 1) responds in 25 µs to enable and 1 µs to disable the clock output - enabling precise, low-overhead clock gating for power management in FPGA and ASIC-based systems.

Is the LMK6CE15625DDLFT compliant with PCIe Gen 7 timing requirements?

Yes, the LMK6CE15625DDLFT meets PCIe Gen 7 common-clock jitter specification (≤67 fs RMS, 12 kHz–20 MHz) at 156.25 MHz. Its measured RMS jitter is ≤500 fs maximum at 100 MHz (12 kHz–20 MHz), and phase noise performance (–100 dBc/Hz at 1 kHz offset) further ensures margin against PCIe Gen 7 SRNS and spectral mask requirements.