CYW256OXCT

Overview

The CYW256OXCT is a 12-output clock buffer designed for distributing high-speed memory clocks in PC applications. It supports up to two DDR DIMMs or three SDRAM DIMMs, featuring low skew outputs under 100 ps and an SMBus interface for individual output control. The device operates with a 3.3V supply for standard SDRAM mode or a 2.5V supply for DDR-only mode. Electrical specifications include a maximum propagation delay of 10 ns, an operating temperature range of 0°C to +70°C, and a supply voltage range of 2.375 V to 3.465 V depending on the selected mode.

Feature Summary

• One input to 12 output buffer/drivers supporting 2 DDR or 3 SDRAM DIMMs
• SMBus interface enables individual output control and power management
• Low skew outputs (< 100 ps) support 266 MHz and 333 MHz DDR SDRAM
• Space-saving 28-pin SSOP package with dedicated power management pin

Applications

• Distributing high-speed clocks in PC applications
• Supporting VIA Pro 266 chipset architectures
• Clock distribution for unbuffered standard SDRAM DIMMs
• Clock distribution for DDR DIMMs

Procurement Notes

Verify that the specific ordering suffix 'T' corresponds to the tape and reel packaging format as defined in the manufacturer's documentation. Confirm the commercial temperature grade (0°C to +70°C) aligns with system requirements. Ensure the host design accommodates the required 2.5V or 3.3V power supply configuration based on the selected memory mode.

Selection Notes

Select this component when designing systems requiring a single source to drive multiple memory modules with precise timing alignment. Choose the 2.5V supply configuration for DDR-only modes and the 3.3V configuration for standard SDRAM modes. Ensure the PCB layout includes appropriate decoupling capacitors and termination resistors as specified in the datasheet application examples to maintain signal integrity at frequencies up to 180 MHz.

Part Context

This part belongs to the W256 family of clock buffers manufactured by Silicon Laboratories Inc. The CYW256OXC variant represents the lead-free version in a standard tube, while the CYW256OXCT specifically denotes the tape and reel packaging option for automated assembly processes within the commercial temperature range.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation.