Texas Instruments LMK6HE400000BDLER

Overview

LMK6HE400000BDLER from Texas Instruments is a fixed-frequency, ultra-low-jitter Bulk-Acoustic Wave (BAW) oscillator delivering 400 MHz HCSL output at 1.8V supply, operating from –40°C to +85°C in a 3.2mm × 2.5mm DLE package. It serves as a PCIe Gen 1–7 compliant reference clock for high-speed SERDES in data center switches, optical transport modules, and FPGA/ASIC timing subsystems.

For engineers reviewing the LMK6HE400000BDLER datasheet, LMK6HE400000BDLER pinout, LMK6HE400000BDLER application, or LMK6HE400000BDLER equivalent, key selection criteria include its 100 fs typical RMS jitter (12 kHz–20 MHz), ±25 ppm total frequency stability over 10 years, HCSL drive capability into 50 Ω, and integrated LDO with –67 dBc PSRR at 500 kHz.

Technical Context

The LMK6HE400000BDLER implements TI's monolithic BAW resonator co-integrated with a high-performance fractional divider and HCSL output driver, enabling factory-programmed 400 MHz operation without external components. Its architecture includes on-die temperature sensing, power conditioning, and configurable function pin logic (Pin 1 = Output Enable, active-high or NC).

It operates under strict 1.7 V–1.9 V supply tolerance and achieves <5 ms start-up time. The device supports differential HCSL signaling with defined VOH/VOL levels, crossing point voltage control, and slew rate regulation - all optimized for signal integrity in 56G/112G PAM4 and PCIe Gen 7 clock distribution paths.

Key Specifications

Pinout & Package

LMK6HE400000BDLER uses a 6-pin VSON (DLE-6) package measuring 3.2 mm × 2.5 mm with wettable flanks. Pin 1 is configured as Output Enable (active-high or NC); pins 4 and 5 deliver complementary HCSL outputs; pin 6 supplies 1.8 V; pin 3 is ground.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-frequency HCSL oscillator applications.

Compared with LMK6HE400000ADLER and Si5341-B-GM, the LMK6HE400000BDLER delivers optimal integration for 1.8 V, space-constrained, fixed-frequency HCSL applications - eliminating configuration overhead while maintaining PCIe Gen 7 timing compliance in the smallest possible footprint.

Availability

LMK6HE400000BDLER is available at Aetrix Electronics and suitable for high-speed data center switches, coherent optical transport modules, and PCIe Gen 7 server backplanes requiring stable component supply, long-term lifecycle assurance, and guaranteed traceable sourcing.

Supply support for LMK6HE400000BDLER 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 high-performance timing solutions, with manufacturing and design centers across North America, Asia, and Europe.

The LMK6H family was engineered specifically for ultra-low-jitter, fixed-frequency clock generation in next-generation networking, optical, and compute platforms - replacing quartz-based oscillators with monolithic BAW technology for superior reliability and integration.

FAQ

What is the output type and drive capability of the LMK6HE400000BDLER?

The LMK6HE400000BDLER provides HCSL differential output with VOH = 460–660 mV and VOL = ±150 mV into a 50 Ω DC-coupled load. It delivers 400 MHz at 1.8 V supply and supports standard HCSL termination schemes without external resistors. This drive strength ensures robust signal integrity across FR4 PCB traces up to 10 inches in length, as validated in TI's LMK6x evaluation module test reports.

Does the LMK6HE400000BDLER meet PCIe Gen 7 timing requirements?

Yes, the LMK6HE400000BDLER is explicitly validated for PCIe Gen 1 through Gen 7 compliance. At 400 MHz, its measured PCIe Gen 7 common-clock jitter is 0.005–0.028 ps (5–28 fs), well below the 67 fs specification limit. This validation is documented in TI's SNAS826G datasheet Section 6.7, Table "HCSL - Clock output jitter", under JPCIe7-cc parameter.

What is the recommended power supply decoupling for LMK6HE400000BDLER?

Texas Instruments recommends placing a 100 nF ceramic capacitor and a 1 µF tantalum or ceramic capacitor in parallel, as close as possible to the VDD (Pin 6) and GND (Pin 3) pins. This dual-capacitor network suppresses high-frequency switching noise and low-frequency ripple, ensuring the integrated LDO maintains –67 dBc PSRR performance at 500 kHz. Layout guidelines are detailed in Section 9.3 of the SNAS826G datasheet.

Can the LMK6HE400000BDLER be used in place of a quartz-based HCSL oscillator?

Yes, the LMK6HE400000BDLER is designed as a direct replacement for quartz-based HCSL oscillators. Its monolithic BAW resonator eliminates aging drift, shock sensitivity, and frequency pullability issues inherent in crystals. With ±25 ppm total stability over 10 years and –40°C to +85°C operation, it exceeds the performance and reliability of typical quartz oscillators in high-vibration, thermally cycling environments like telecom line cards.

What is the function of Pin 1 on the LMK6HE400000BDLER?

Pin 1 on the LMK6HE400000BDLER is designated OE / ST / NC and is configured as Output Enable (active-high) for this variant. When driven to VDD (1.8 V), the HCSL outputs activate; when pulled low or left floating (NC), output is disabled. This behavior is confirmed in Table 5-1 of the SNAS826G datasheet and applies specifically to LMK6H variants with 'E' suffix (e.g., LMK6HExxxxxBxxR).