ICS557G-03

Overview

The ICS557G-03 is a spread spectrum clock generator designed for PCI Express Gen 1 and Ethernet applications. It accepts a 25 MHz crystal or clock input and generates two differential HCSL outputs at selectable frequencies of 25, 100, 125, or 200 MHz. The device operates on a 3.3 V supply with a maximum operating temperature of 70°C. Key electrical parameters include an input frequency of 25 MHz, cycle-to-cycle jitter of 80 ps, and a modulation frequency range of 30 to 33 kHz.

Feature Summary

• Supports HCSL output levels with selectable frequencies up to 200 MHz
• Integrated Phase-Locked Loop (PLL) for low jitter performance
• Spread spectrum capability configurable via external pins
• Packaged in a 16-pin TSSOP format

Applications

• PCI Express Gen 1 systems
• Ethernet infrastructure equipment
• PC and embedded system designs requiring EMI reduction

Procurement Notes

Verify the specific ordering suffix to confirm package type and temperature range. Suffixes such as 'LF' indicate lead-free compliance, while 'T' denotes tape and reel packaging. Confirm that the commercial temperature range (0°C to +70°C) aligns with the target application environment before procurement.

Selection Notes

Select this component when a single-ended 25 MHz input is available and two differential HCSL outputs are required. Ensure the load capacitance requirements for the external crystal match the formula provided in the datasheet. Verify that the 78 mA typical supply current fits within the system power budget.

Part Context

This part belongs to the IDT/ICS 557-03 series of PCI Express clock sources. It serves as a foundational timing solution for legacy PCIe Gen 1 interfaces. The device integrates the oscillator and PLL functions, reducing the need for multiple discrete components in the clock generation path.

Replacement Considerations

Public confirmed substitute part numbers: NB3N51032DTG, NB3N51032DTR2G.