Infineon Technologies CY2309CZXI-1T

Overview

CY2309CZXI-1T from Cypress Semiconductor is a 3.3V industrial-grade zero-delay clock buffer with PLL-based architecture, accepting one 5V-tolerant reference input and distributing it across nine low-skew outputs (4+4+1 banked configuration), supporting 10–133 MHz operation for PCI, SDRAM, and Pentium-compatible systems.

For engineers reviewing the CY2309CZXI-1T datasheet, CY2309CZXI-1T pinout, CY2309CZXI-1T application, or CY2309CZXI-1T equivalent, key selection criteria include output bank control via S1/S2 select inputs, PLL bypass capability for test mode, ±350 ps input-output delay tolerance, and guaranteed <85 ps output-to-output skew under matched loading.

Technical Context

The CY2309CZXI-1T integrates an on-chip PLL with internal feedback sourced from the CLKOUT pin to achieve zero input-output propagation delay. Its dual-bank output structure (Bank A: CLKA1–CLKA4; Bank B: CLKB1–CLKB4) enables selective three-state control of Bank B via S1/S2 decoding.

It supports PLL shutdown when REF has no rising edges (reducing IDD to ≤25.0 μA) and enters reference-pass-through mode when S2=1/S1=0-bypassing the PLL to drive outputs directly from REF. All outputs feature weak pull-downs; S1/S2 have weak pull-ups.

Key Specifications

Pinout & Package

Package: 16-pin 4.4-mm TSSOP (lead pitch: 0.65 mm), RoHS-compliant, industrial temperature rated.

Key Features

Applications

Equivalent & Alternatives

CY2309CZXI-1T has two verified drop-in alternatives differing in drive strength and temperature grade.

Compared with CY2309SCXI-1T and CY2309CZXI-1H, the CY2309CZXI-1T uniquely balances industrial reliability, moderate drive strength, and jitter performance-making it optimal for fixed-temperature embedded systems where robustness matters more than peak speed or cost minimization.

Availability

CY2309CZXI-1T is available at Aetrix Electronics and suitable for PCI bus clock distribution, SDRAM memory controller timing, and Pentium-compatible system clocking requiring stable component supply across industrial temperature ranges and long production lifecycles.

Supply support for CY2309CZXI-1T 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) designs high-reliability timing, memory, and programmable logic solutions for industrial, automotive, and communications markets.

The CY2309 product line delivers zero-delay clock buffering for legacy and mixed-technology systems-specifically targeting applications needing deterministic clock fanout without FPGA or microcontroller intervention.

FAQ

What is the function of the CLKOUT pin beyond clock output?

The CLKOUT pin serves as the internal feedback node for the on-chip PLL. Its capacitive loading directly controls the input-output propagation delay: matching its load to other outputs achieves zero delay, while intentional mismatch enables fine-grained skew tuning. It must be loaded even if unused.

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

S1/S2 determine whether the PLL remains active or is bypassed. In PLL bypass mode (S2=1, S1=0), the device draws slightly higher dynamic current but avoids PLL lock-time delays. In all other modes, the PLL operates normally; power-down occurs only when REF stalls, reducing current to ≤25.0 μA regardless of S1/S2 state.

Can CY2309CZXI-1T drive 50 Ω transmission lines directly?

No. The outputs are CMOS-compatible with 8 mA sink/source capability (–1 variant) and are designed for capacitive loads up to 30 pF below 100 MHz. For 50 Ω lines, external series termination or buffer amplification is required to prevent signal degradation and excessive current draw.

Why is equal loading required across all outputs for zero skew?

Process, voltage, and temperature variations cause slight differences in output driver delay. Equal capacitive loading minimizes these mismatches by ensuring identical RC time constants at each output pad. Uneven loading introduces differential slew rate effects, increasing measured output-to-output skew beyond the specified 85 ps typical.