Infineon Technologies CY28442ZXCT

Overview

CY28442ZXCT from Cypress Semiconductor is a clock generator IC compliant with Intel CK410M for Pentium-M platforms, delivering differential CPU clocks (up to 200 MHz), 100-MHz/96-MHz spreadable SRC clocks, 48-MHz USB, 33-MHz PCI, and 96-MHz dot clocks in a single 56-pin TSSOP package.

For engineers reviewing the CY28442ZXCT datasheet, CY28442ZXCT pinout, CY28442ZXCT application, or CY28442ZXCT equivalent, key selection criteria include I²C programmability, per-output clock enable/disable via SMBus registers, VTT_PWRGD#-latched frequency select (FS_A/B/C), and independent CLKREQ#-based SRC clock gating for power-aware timing control.

Technical Context

The CY28442ZXCT integrates four PLLs: PLL1 for CPU clock synthesis, PLL2 for reference clock generation, PLL4 for 96/100-MHz spread-spectrum SRC clocks, and a fixed-divider path for USB and PCI outputs. It uses a 14.318-MHz crystal input (XIN/XOUT) as primary reference.

Frequency selection is latched on VTT_PWRGD# assertion, freezing FS_A/FS_B/FS_C states to configure CPU (100/133/166/200 MHz), SRC (100 MHz), PCI (33 MHz), REF (14.318 MHz), DOT96 (96 MHz), and USB_48 (48 MHz) outputs per Table 1. All differential outputs are LVDS-compatible with internal 100-Ω termination.

Key Specifications

Pinout & Package

56-pin TSSOP (Thin Shrink Small Outline Package) with exposed thermal pad; pin-compatible with Intel CK410M clock requirements and designed for surface-mount assembly on high-density motherboard layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar clock generator applications.

Compared with ICS952006AGT and ICS954201AGT, the CY28442ZXCT uniquely combines Intel CK410M-compliant CPU clock synthesis, I²C-configurable SRC gating, Lexmark-optimized spread spectrum, and dedicated SATA reference outputs - enabling full Alviso platform timing consolidation in one device.

Availability

CY28442ZXCT is available at Aetrix Electronics and suitable for mobile computing platforms, industrial embedded PCs, flat-panel display controllers, and SATA storage subsystems requiring stable component supply and long-term lifecycle support.

Supply support for CY28442ZXCT includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Cypress Semiconductor (now part of Infineon) designs high-performance timing, memory, and programmable logic solutions for computing, automotive, and industrial markets.

The CY28442 belongs to Cypress's CK410M-compliant clock generator product line, engineered specifically to replace discrete clock trees in Intel Pentium-M–based notebooks and embedded systems.

FAQ

What is the function of the VTT_PWRGD# pin?

VTT_PWRGD# is a level-sensitive strobe that latches the states of FS_A, FS_B, FS_C, ITP_EN, and 96_100_SEL inputs at power-up. Once asserted low, it freezes configuration; subsequent transitions are ignored except in test mode. It also serves as a real-time power-down enable when driven high after latching.

Can the 96-MHz DOT96 output be spread-spectrum modulated?

No. The DOT96T/DOT96C outputs are fixed-frequency, non-spread 96-MHz differential clocks intended for flat-panel display timing. Spread spectrum is only available on the 96_100_SSC outputs (pins 17/18), which are separate and configurable via SMBus register Byte 0 bit 0.

How many differential clock outputs does CY28442ZXCT support?

The CY28442ZXCT supports 14 dedicated differential clock outputs: three CPU clock pairs (CPUT0/CPUC0 through CPUT2/CPUC2), five SRC clock pairs (SRCT1/SRCC1 through SRCT5/SRCC5), one DOT96 pair, and one 96/100-MHz SSC pair - totaling 14 pins configured as seven differential pairs.

Is the I²C interface functional during system operation?

Yes, the SMBus interface remains fully operational after power-up and supports byte/block read/write operations for runtime configuration. However, it is not intended for dynamic power management during active CPU operation; register changes are typically performed during BIOS initialization or system suspend/resume sequences.