Infineon Technologies CY2304SI-1

Overview

CY2304SI-1 from Cypress Semiconductor is a 3.3V industrial-grade zero-delay clock buffer with on-chip PLL, designed for high-speed clock distribution in telecom and datacom systems. It delivers four low-skew LVCMOS outputs (two per bank), supports 10–133.3 MHz input frequencies, guarantees ≤200 ps output-to-output skew, and operates across –40°C to +85°C.

For engineers reviewing the CY2304SI-1 datasheet, CY2304SI-1 pinout, CY2304SI-1 application, or CY2304SI-1 equivalent, this device is selected for precise clock fanout where deterministic phase alignment, multi-device synchronization (<500 ps inter-device skew), and industrial temperature stability are required.

Technical Context

The CY2304SI-1 uses an internal PLL to lock REF input to FBK feedback, achieving zero input-output propagation delay when FBK is sourced from one of its own outputs and loading is matched. Its dual-bank architecture (CLKA1/CLKA2 and CLKB1/CLKB2) enables independent bank-level timing control.

It enters power-down mode with <25 μA supply current when REF stops toggling, tri-stating all outputs. The device requires external capacitive load balancing between FBK and output pins to fine-tune input-output delay-critical for system-level timing closure in synchronous backplane designs.

Key Specifications

Pinout & Package

8-pin 150-mil SOIC package with standard JEDEC MS-012 footprint and 1.27 mm pitch; RoHS-compliant, 0.07 g mass, 0°–8° lead angle.

Key Features

Applications

Equivalent & Alternatives

Cypress CY2304SI-1 has two verified drop-in alternatives with documented functional and parametric differences.

Compared with IDT 8T49N241 and ON Semi NB3N3010B, CY2304SI-1 uniquely delivers true zero-delay operation at up to 133.3 MHz with ≤200 ps skew-making it irreplaceable in high-frequency telecom and datacom clock trees requiring deterministic phase alignment.

Availability

CY2304SI-1 is available at Aetrix Electronics and suitable for telecom line cards, industrial Ethernet controllers, and base station radio units requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CY2304SI-1 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 high-performance timing, memory, and programmable logic solutions for communications and industrial markets.

The CY2304 product line was engineered specifically for zero-delay clock distribution in high-speed digital systems-targeting applications where phase coherence, low jitter, and multi-device synchronization are non-negotiable design constraints.

FAQ

What is the maximum load capacitance supported at 133.3 MHz?

The CY2304SI-1 supports up to 15 pF load capacitance at 133.3 MHz, as specified in the industrial temperature switching characteristics table. Exceeding this value degrades rise/fall times and increases jitter beyond guaranteed limits-designers must use controlled-impedance traces and minimize stub lengths to stay within this constraint.

Can CY2304SI-1 operate with a 2.5V reference input?

No. While the REF pin is 5V-tolerant, the CY2304SI-1 requires a minimum VIH of 2.0 V and operates only from a 3.3V supply (VDD = 3.0–3.6 V). A 2.5V logic signal may not meet the VIH threshold reliably across temperature and voltage corners, risking metastability or PLL unlock.

How is zero delay achieved without internal delay compensation circuits?

Zero delay is achieved by closing the PLL feedback loop using one of the device's own outputs (e.g., CLKA1 → FBK). The PLL dynamically adjusts its phase to force the rising edge at FBK to align precisely with the REF input edge-eliminating fixed propagation delay. This requires matched capacitive loading on FBK and driven outputs to prevent static phase offset.

Does CY2304SI-1 support spread-spectrum clocking (SSC)?

No. The CY2304SI-1 does not implement spread-spectrum modulation. Its PLL is optimized for low-jitter, fixed-frequency clock replication. Introducing SSC on the REF input causes PLL instability and increased cycle-to-cycle jitter-this device is intended for clean, stable reference sources only.