557G-05ALF

Overview

The Renesas Electronics 557G-05ALF is a quad differential PCI-Express Gen1 clock source belonging to the 557-05A series. It functions as a spread-spectrum clock generator designed to reduce electromagnetic interference (EMI) in PC and embedded systems. The device provides four differential HCSL or LVDS high-frequency outputs with selectable output frequency and spread type via external pins. Key electrical parameters include a maximum output frequency of 200 MHz, a maximum input frequency of 25 MHz, and a typical jitter of 80 ps. It operates on a single 3.3 V supply with a working current of 105 mA and is housed in a TSSOP-20 package.

Feature Summary

• Quad differential outputs supporting HCSL or LVDS signaling
• Spread-spectrum capability for EMI reduction in PCIe Gen1 applications
• External pin-selectable output frequency and spread type
• Low jitter performance with 80 ps cycle-to-cycle specification

Applications

• PCI Express Gen1 clock generation
• PC motherboard clock distribution
• Embedded system EMI mitigation

Procurement Notes

Verify the specific suffix against official documentation to confirm package type and temperature range. The 'LF' designation indicates lead-free compliance, while 'T' variants denote tape-and-reel packaging. Confirm RoHS status and moisture sensitivity level requirements prior to integration into the design flow.

Selection Notes

Select this component when a quad-output clock source is required for PCIe Gen1 interfaces. Ensure the design supports the 25 MHz crystal input and 3.3 V supply voltage. Compare against the 557G-03 series if only two differential outputs are sufficient for the application.

Part Context

This part belongs to the Renesas 557-05A family of clock generators. It serves as a successor to earlier IDT designs acquired by Renesas. The 557G-05ALF specifically targets high-speed digital interfaces requiring low-jitter, spread-spectrum clocking to meet regulatory emissions standards.

Replacement Considerations

The 557GI-05ALFT is a verified alternative within the same family offering identical functionality in a tape-and-reel package.