Infineon Technologies CY2309CZXC-1HT

Overview

CY2309CZXC-1HT from Cypress Semiconductor is a 3.3V zero-delay clock buffer IC with PLL-based architecture, distributing one reference clock to nine low-skew outputs (4+4+1 banked configuration) across 10–133 MHz. It features 85 ps typical output-to-output skew, 60 ps typical cycle-to-cycle jitter (high-drive), and test-mode PLL bypass for system validation. Used in Pentium-based CPU clock distribution and PCI/SDRAM timing subsystems.

For engineers reviewing the CY2309CZXC-1HT datasheet, CY2309CZXC-1HT pinout, CY2309CZXC-1HT application, or CY2309CZXC-1HT equivalent, key selection criteria include guaranteed device-to-device skew <700 ps, industrial temperature support (–40°C to +85°C), high-drive slew rate (1 V/ns), and configurable bank enable via S1/S2 select inputs.

Technical Context

The CY2309CZXC-1HT integrates an on-chip PLL with internal feedback routed from the CLKOUT pin, enabling zero input-output propagation delay when all outputs-including CLKOUT-are equally loaded. Its dual-bank output structure (Bank A: CLKA1–CLKA4; Bank B: CLKB1–CLKB4) supports independent enable/disable control via S1/S2 logic decoding.

It operates in PLL mode by default but enters reference-pass-through mode when S2=1 and S1=0, directly routing REF to all active outputs while disabling the PLL-critical for board-level clock testing. Power-down occurs automatically when REF has no rising edges, reducing supply current to <25.0 μA.

Key Specifications

Pinout & Package

Package: 16-pin TSSOP (4.4 mm width), RoHS-compliant, surface-mountable with standard reflow profile.

Key Features

Applications

Equivalent & Alternatives

CY2309CZXC-1HT has two verified functional alternatives with documented parameter and application differences:

Compared with ICS553M-01ILFT and PI6C20400LEX, CY2309CZXC-1HT uniquely balances industrial temperature operation, configurable bank enable, PLL bypass for test, and 133 MHz capability-making it optimal for upgradeable, test-aware clock trees in embedded computing.

Availability

CY2309CZXC-1HT is available at Aetrix Electronics and suitable for PCI bus clock distribution, SDRAM memory controller timing, and Pentium-based CPU clock tree applications requiring stable component supply, long-term lifecycle assurance, and industrial temperature qualification.

Supply support for CY2309CZXC-1HT 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 Technologies) is a U.S.-based semiconductor company specializing in timing, memory, and microcontroller solutions for industrial, automotive, and communications markets.

CY2309 belongs to Cypress's legacy zero-delay buffer product line, designed specifically for high-fidelity clock distribution in cost-sensitive, high-volume computing and industrial control platforms.

FAQ

What is the purpose of the CLKOUT pin beyond feedback?

The CLKOUT pin serves as the internal PLL feedback node and must be loaded identically to other outputs to achieve zero input-output delay. Even when unused, it requires a capacitive load matching the other outputs (e.g., 10 pF for >100 MHz operation). Its voltage swing and edge rate are identical to CLKA/CLKB outputs, making it usable as a tenth clock output if needed.

How does the S1/S2 select logic affect power consumption?

When S2=1 and S1=0, the device enters PLL bypass mode-disabling the PLL while driving all active outputs directly from REF. This reduces dynamic current by eliminating PLL overhead, though static supply current remains unchanged. In contrast, S2=0/S1=0 places Bank B in three-state, cutting its output driver current and lowering total IDD proportionally to unloaded outputs.

Can CY2309CZXC-1HT drive 50 Ω transmission lines directly?

No. The CY2309CZXC-1HT is designed for CMOS loads with specified 10–30 pF capacitance-not 50 Ω resistive termination. Driving 50 Ω lines directly causes excessive current draw, signal distortion, and violates VOL/VOH specs. Use series resistors (e.g., 33 Ω) or dedicated clock drivers for controlled-impedance traces.

Why does output skew increase above 250 ps in some configurations?

Output-to-output skew exceeds the 85 ps typical value-and may reach 250 ps maximum-when outputs are unequally loaded, mismatched in trace length or topology, or driven into different load types (e.g., mixed capacitive and resistive). The 85 ps spec assumes identical 10/30 pF loads, same PCB layer, and matched fanout routing per Cypress application note AN1078.