PI6C557-05LE

Overview

The PI6C557-05LE is a spread spectrum clock generator compliant with PCI Express 2.0 and Ethernet standards, manufactured by Diodes Incorporated. It features a single PLL circuit that accepts a 25MHz crystal or HCSL input to generate four differential outputs (HCSL or LVDS). The device supports selectable output frequencies of 100MHz and 200MHz with spread spectrum options of -0.5%, -1.0%, -1.5%, or no spread. Operating on a 3.3V supply (3.135V–3.465V), it delivers typical RMS jitter of 2.1ps and cycle-to-cycle jitter of 40ps. Packaged in a 20-TSSOP, it operates within an industrial temperature range of -40°C to +85°C.

Feature Summary

• PCIe 2.0 Compliant: Designed for PC and embedded systems to reduce electromagnetic interference (EMI) via spread spectrum generation.
• Flexible Output Configuration: Provides four differential pairs supporting both HCSL (0.7V current mode) and LVDS compatible voltage levels.
• Configurable Spread Spectrum: External pins (S0-S2) allow selection of down-spread rates (-0.5%, -1.0%, -1.5%) or no spread at 100MHz or 200MHz.
• Low Jitter Performance: Achieves typical RMS jitter of 2.1ps and cycle-to-cycle jitter of 40ps using patented PLL techniques.

Applications

• PCI Express (PCIe) 2.0 expansion cards and system clocks
• Ethernet interface clock generation
• PC and embedded system motherboard timing

Procurement Notes

Verify the ordering suffix 'E' confirms lead-free and green packaging as specified in the datasheet. The 'LE' variant indicates the standard tube packaging; add an 'X' suffix if tape and reel packaging is required. Confirm the package code 'L' corresponds to the 20-pin, 173-mil wide TSSOP form factor for PCB layout compatibility.

Selection Notes

Select this component when PCIe 2.0 compliance and EMI reduction are required. Ensure the design supports a 25MHz fundamental mode parallel resonant crystal with less than 30PPM error. Verify that the target application can accommodate the external termination resistors (RS=33Ω, RT=49.9Ω for PCIe) or pull-up/pull-down networks required for LVDS operation.

Part Context

This part belongs to the PI6C557 series of clock generators from Diodes Incorporated (formerly Pericom Semiconductor). The series includes variants with different output counts and packages, such as the 2-output PI6C557-03 and 1-output PI6C557-01. The PI6C557-05 specifically provides four differential outputs, distinguishing it from lower-channel count family members.

Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation. When evaluating alternatives, ensure the replacement supports PCIe 2.0, offers four differential outputs, and matches the 20-TSSOP package dimensions.