Infineon Technologies CY2309SXC-1T

Overview

CY2309SXC-1T from Infineon Technologies (formerly Cypress) is a 3.3 V zero-delay clock buffer IC with nine low-skew outputs, integrated PLL, and dual-bank output control. It operates from 10 MHz to 133 MHz, delivers ≤85 ps typical output-to-output skew, supports 5-V-tolerant REF input, and features test-mode bypass and power-down mode drawing <25.0 μA. Used in Pentium-based CPU clock distribution.

For engineers reviewing the CY2309SXC-1T datasheet, CY2309SXC-1T pinout, CY2309SXC-1T application, or CY2309SXC-1T equivalent, key selection criteria include zero-input-output delay calibration via CLKOUT loading, bank-selectable output enable (S1/S2), industrial temperature range (–40°C to +85°C), and TSSOP-16 package compatibility with high-density PCB layouts.

Technical Context

The CY2309SXC-1T implements an on-chip PLL with internal feedback sourced from the CLKOUT pin, enabling precise zero-delay operation when all outputs-including CLKOUT-are uniformly loaded. Its dual-bank architecture (Bank A: CLKA1–CLKA4; Bank B: CLKB1–CLKB4) allows independent enable/disable via S1/S2 select inputs.

It supports three operational states: full PLL-driven output (S2=0,S1=0 or 0,1), reference-bypass mode (S2=1,S1=0), and PLL shutdown (S2=1,S1=1). Power-down occurs automatically when REF has no rising edges, tri-stating all outputs and reducing IDD to <25.0 μA.

Key Specifications

Pinout & Package

Package: 16-pin 4.4-mm TSSOP (RoHS-compliant, lead-free, moisture sensitivity level 3).

Key Features

Applications

Equivalent & Alternatives

Two functionally aligned alternatives are confirmed for CY2309SXC-1T in industrial temperature and TSSOP-16 packaging.

Compared with IDT 85311AMLFT and ON Semi NB3N502DR2G, the CY2309SXC-1T uniquely provides programmable bank control, PLL bypass for production test, and calibrated zero-delay operation-making it irreplaceable in systems requiring dynamic clock management and precise inter-bank skew control.

Availability

CY2309SXC-1T is available at Aetrix Electronics and suitable for PCI bus clock distribution, Pentium-based CPU systems, and industrial PLC backplane designs requiring stable component supply, long-lifecycle support, and RoHS-compliant TSSOP packaging.

Supply support for CY2309SXC-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

Infineon Technologies is a global semiconductor leader headquartered in Munich, Germany, specializing in power management, sensing, connectivity, and security solutions for automotive, industrial, and IoT markets.

The CY2309 product line was originally developed by Cypress Semiconductor and continues under Infineon's Clock & Timing portfolio, targeting high-reliability clock distribution in industrial computing, legacy x86 platforms, and deterministic real-time systems.

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 matched capacitive load (e.g., 30 pF below 100 MHz) to maintain PLL stability and skew performance. It is not intended as a general-purpose clock output unless explicitly routed in the design.

How does S1/S2 control affect power consumption?

S1/S2 directly determine power state: S2=1,S1=1 forces PLL shutdown and tri-states all outputs, reducing IDD to <25.0 μA. In contrast, S2=0,S1=0 enables both banks but draws ~35 mA at 66.67 MHz. This enables hardware-based power gating without software intervention or external logic.

Can CY2309SXC-1T drive 50 Ω transmission lines?

No - the CY2309SXC-1T is specified for capacitive loads only (max 30 pF below 100 MHz, 10 pF above). Driving 50 Ω lines would exceed its output current capability (12 mA max), distort edges, and violate AC timing specs. Use dedicated clock drivers (e.g., SY100EL15) for transmission-line termination.

Is the REF input compatible with CMOS or TTL logic levels?

The REF input is 5-V tolerant with a VDD/2 threshold (~1.65 V at 3.3 V supply), making it compatible with both 3.3 V CMOS and 5 V TTL logic families. Input hysteresis is not specified, so clean signal edges and minimized noise on REF are essential to prevent metastability or false PLL locking.