9ZXL1231AKILFT

Overview

The Renesas 9ZXL1231AKILFT is a second-generation zero-delay clock buffer from the 9ZXL series, designed for high-performance computing and PCIe applications. It features a single differential HCSL input and twelve differential LP-HCSL outputs, operating at frequencies up to 150 MHz. The device integrates an on-chip PLL with selectable bandwidth to minimize jitter peaking in cascaded topologies. Powered by a 1.05V to 3.3V supply, it supports spread spectrum input tracking for EMI reduction. The component is housed in a compact 64-VFQFPN (9x9 mm) package with exposed pad, suitable for surface-mount assembly.

Feature Summary

• 1:12 Input-to-Output Ratio: Converts one differential HCSL input to twelve differential LP-HCSL outputs, eliminating external termination resistors.
• Integrated PLL with Selectable Bandwidth: Allows hardware or SMBus control of PLL bandwidth and bypass modes without power cycling.
• Spread Spectrum Compatibility: Tracks spreading input clocks to reduce electromagnetic interference (EMI).
• Hardware Control: Features nine selectable SMBus addresses and individual output enable pins for flexible system configuration.

Applications

• Intel QuickPath Interconnect (QPI)
• PCI Express (PCIe) Systems
• Servers and High-Performance Computing Platforms

Procurement Notes

Verify the suffix 'KILFT' corresponds to the tape-and-reel packaging format required for automated assembly. Confirm moisture sensitivity level (MSL 3) handling requirements during storage and soldering. Ensure the specific revision matches design specifications, as Renesas may issue Product Change Notices affecting labeling or assembly sites.

Selection Notes

Select this model when a 150 MHz maximum frequency and LP-HCSL output signaling are required for QPI or PCIe Gen 1–5 compliance. Compare against the 9ZXL1231EKILFT if operation at -40°C to +85°C and 400 MHz frequency is necessary, noting the voltage range difference. Verify that the 64-VFQFPN footprint fits the PCB layout constraints.

Part Context

This part belongs to the 9ZXL1231 family of zero-delay buffers. It serves as a low-power upgrade to previous generations, offering improved phase jitter performance. The 'A' variant typically denotes specific electrical characteristics or packaging options within the broader 9ZXL1231 product line, distinct from the 'E' variant which supports extended temperature ranges.

Replacement Considerations

The 9ZXL1231EKILFT is documented as a similar replacement option. Verify compatibility regarding operating temperature range (-40°C to +85°C vs. 0°C to 70°C) and maximum frequency (400 MHz vs. 150 MHz). Check supply voltage tolerances, as the EKILFT variant specifies a narrower 3.135V to 3.465V range compared to the AKILFT's 1.05V to 3.3V range.