W256H

Overview

The W256H is a 1-to-12 clock buffer manufactured by Cypress Semiconductor, designed for distributing high-speed clocks in PC applications. It supports up to two DDR DIMMs or three SDRAM DIMMs and features low skew outputs under 100 ps. The device operates with a single supply voltage of either 3.3V or 2.5V, depending on the configured mode. It includes an SMBus interface for individual output control and power management support via a dedicated pin. The component is housed in a space-saving 28-pin SSOP package.

Feature Summary

• Supports up to 2 DDR DIMMs or 3 SDRAM DIMMs
• Low skew outputs (< 100 ps)
• SMBus interface for individual output control
• Dedicated pin for power management support

Applications

• PC motherboard clock distribution
• DDR SDRAM memory systems
• Standard SDRAM memory systems

Procurement Notes

Verify that the source material confirms the manufacturer as Cypress Semiconductor Corporation. Confirm the operating temperature range is commercial (0°C to 70°C). Ensure the package type matches the 28-pin SSOP specification found in the datasheet.

Selection Notes

Select the W256H when designing systems requiring a single input to drive multiple memory modules. Choose this part if the design requires independent control of output clocks via SMBus or needs specific power-down capabilities. Ensure the system voltage aligns with either 3.3V for standard SDRAM or 2.5V for DDR-only modes.

Part Context

The W256H belongs to the W256 family of clock buffers from Cypress Semiconductor. It is specifically engineered to handle high-speed clock signals for memory interfaces. The device is often used in conjunction with clock synthesizers like the W250-02 for VIA Pro 266 chipset implementations.

Replacement Considerations

The CYW256OXC and CYW256OXCT are lead-free versions of the same component. The W256HT variant offers the same functionality but in a tape and reel packaging format.