PI6C557-03AQEX

Overview

The PI6C557-03AQEX is a PCIe 2.0 compliant spread spectrum clock generator manufactured by Diodes Incorporated. It accepts a 25 MHz crystal or clock input and provides two differential HCSL outputs at selectable frequencies of 25, 100, 125, or 200 MHz. The device operates on a 3.3V supply (3.0V to 3.6V) with a typical operating current of 95 mA. It features a typical cycle-to-cycle jitter of 35 ps and RMS jitter of 2.1 ps. The component is housed in a 16-pin QSOP package and supports an industrial temperature range from -40°C to +85°C.

Feature Summary

• PCIe 2.0 Compliant: Supports PCI Express Gen 2 and Ethernet requirements for EMI reduction.
• Spread Spectrum Capability: Configurable via external pins for -0.5%, -0.75%, or no spread.
• Low Jitter Performance: Typical phase jitter of 2.1 ps RMS and 35 ps cycle-to-cycle.
• Flexible Output Configuration: Provides two differential HCSL pairs; LVDS compatible levels supported.

Applications

• PCI Express Gen 2 systems
• Ethernet applications
• PC and embedded systems requiring EMI reduction

Procurement Notes

Verify the 'Q' suffix indicates the 16-pin QSOP package configuration. Confirm the 'X' suffix denotes tape and reel packaging. Ensure the specific revision level matches design requirements as manufacturers may update documentation without notice.

Selection Notes

Select this model when a 16-pin QSOP footprint is required for PCIe 2.0 designs. Verify that the board layout accommodates the specific output termination resistors and crystal load capacitance values recommended in the datasheet for optimal signal integrity.

Part Context

This part belongs to the PI6C557-03A family of clock generators. The 'Q' suffix specifically identifies the 16-pin QSOP package variant, while the 'ALE' suffix corresponds to the TSSOP package version within the same product line.

Replacement Considerations

PI6C557-03ALEX serves as the direct pin-compatible alternative utilizing a 16-pin TSSOP package instead of QSOP.

FAQ

How are the output frequency and spread spectrum settings configured?

Output frequency is selected using S1 and S0 pins, while spread spectrum selection (-0.5%, -0.75%, or none) is determined by SS1 and SS0 pins. All these pins have internal pull-up resistors.

What is the maximum operating voltage for the PI6C557-03AQEX?

The absolute maximum rating for the supply voltage is 3.6V, with a recommended operating range of 3.0V to 3.6V centered around 3.3V.

Does the device support LVDS outputs?

Yes, the device provides HCSL outputs but can be configured for LVDS compatible voltage levels through specific layout guidelines provided in the datasheet.