ICS557G-05AT

Overview

The ICS557G-05AT is a quad differential PCI-Express spread-spectrum clock generator designed for PC and embedded systems to reduce electromagnetic interference. It accepts a 25 MHz crystal or clock input and provides four differential HCSL or LVDS outputs at selectable frequencies of 100 MHz or 200 MHz. The device operates on a single 3.3 V supply (3.135V ~ 3.465V) within the commercial temperature range of 0°C to 70°C. Configuration of output frequency and spread spectrum type is achieved via external pins, supporting PCIe Gen1 requirements.

Feature Summary

• Four differential spread-spectrum clock outputs with selectable HCSL or LVDS signaling
• Supports PCI-Express applications with EMI reduction capabilities
• Frequency and spread selection controlled by external S0, S1, and S2 pins
• Operates with a 25 MHz crystal or clock input

Applications

• PCI Express (PCIe) clock sources in PC systems
• Embedded systems requiring low EMI clock distribution
• High-frequency clock generation for peripheral interfaces

Procurement Notes

Verify the specific ordering suffix against the manufacturer's datasheet to confirm package type and temperature rating. The 'T' suffix typically indicates tape and reel packaging, while 'LF' denotes lead-free compliance. Ensure the selected variant matches the required operating temperature range and shipping format for your assembly process.

Selection Notes

Select this component when a quad differential clock source with spread-spectrum capability is needed for PCIe Gen1 designs. Compare the 100 MHz and 200 MHz output options based on target system requirements. Verify that the 20-TSSOP package dimensions fit the PCB layout constraints and that the commercial temperature range meets environmental specifications.

Part Context

This part belongs to the ICS557 series of PCI-Express clock generators. It serves as a high-performance alternative to standard oscillators by providing programmable spread spectrum to minimize EMI peaks. The device integrates PLL synthesis and oscillator circuits into a compact surface-mount package.

Replacement Considerations

Direct replacements include other parts from the ICS557 family, such as the ICS557G-05A (tube package) or ICS557GI-05ALFT (industrial temperature, lead-free). Ensure pin compatibility and electrical characteristics match before substitution.