LMKDB1202REYR

Overview

The LMKDB1202 is a low-power, high-compliance LP-HCSL clock multiplexer supporting PCIe Gen 1 through Gen 7. It features two differential inputs and two differential outputs within a 3mm x 3mm VQFN-20 package. The device provides extremely low additive jitter, with maximums of 5fs for PCIe Gen 5 and 3fs for PCIe Gen 6 at 156.25MHz. It supports both Common Clock (CC) and Independent Reference (IR) architectures, accepts input clocks with or without Spread Spectrum Clocking (SSC), and offers selectable 85Ω or 100Ω output impedance. Power supply options include 1.8V and 3.3V ±10%.

Feature Summary

• Supports PCIe Gen 1 to Gen 7 with DB2000QL compliance
• Extremely low additive jitter: 5fs max for Gen 5, 3fs max for Gen 6
• Flexible power-up sequence with fail-safe inputs and automatic output disable
• Selectable 85Ω or 100Ω output impedance via ZOUT_SEL pin

Applications

• High Performance Computing
• Server Motherboard
• NIC/SmartNIC
• Hardware Accelerator

Procurement Notes

Verify the REY suffix corresponds to the 20-pin VQFN package. Confirm that the specific revision matches the SNAS927A datasheet dated April 2026. Ensure compatibility with required operating temperatures ranging from -40°C to 105°C ambient.

Selection Notes

Select this model for designs requiring only two differential outputs. Compare against LMKDB1204 (4 outputs) or LMKDB1208 (8 outputs) if higher fan-out is needed. Verify that the 3mm x 3mm footprint fits the PCB layout constraints. Check if SMBus control is required, noting that the LMKDB1202 lacks dedicated SMBus pins compared to larger variants.

Part Context

Part of the LMKDB family of ultra-low jitter clock muxes. Includes LMKDB1204 (REX package) and LMKDB1208 (RSL package). All devices share similar electrical characteristics and support PCIe Gen 1-7 standards.

Replacement Considerations

LMKDB1204 (REX package) offers four outputs in a 4x4mm VQFN. LMKDB1208 (RSL package) provides eight outputs in a 6x6mm VQFN. Both maintain identical jitter performance and PCIe Gen 1-7 support.