Infineon Technologies CY2305CSXC-1HT

Overview

CY2305CSXC-1HT from Cypress Semiconductor is a 3.3 V zero-delay clock buffer IC with one input and five low-skew buffered outputs, operating from 10 MHz to 133 MHz, featuring 50 ps typical cycle-to-cycle jitter at 66 MHz (15 pF load), on-chip PLL with internal feedback via CLKOUT pin, and power-down mode drawing <12 µA at 0 MHz REF input. It is used in high-speed digital systems requiring precise clock distribution, such as FPGA-based control boards and industrial PLC timing modules.

For engineers reviewing the CY2305CSXC-1HT datasheet, CY2305CSXC-1HT pinout, CY2305CSXC-1HT application, or CY2305CSXC-1HT equivalent, key selection criteria include input frequency range (10–133 MHz), output count (5), zero-delay architecture with internal PLL feedback, commercial temperature grade (0°C to +70°C), and 8-pin SOIC package compatibility with standard PCB layout practices.

Technical Context

The CY2305CSXC-1HT implements an on-chip PLL locked to the REF input, with feedback sourced internally from the CLKOUT pin to achieve zero input-to-output propagation delay. Its output skew is minimized by uniform capacitive loading across all outputs-including CLKOUT-even when unused.

It supports automatic power-down when REF has no rising edges, tri-stating all outputs and reducing supply current to <12 µA. The -1H suffix denotes higher drive strength: 12 mA sink/source capability versus 8 mA for -1 versions, enabling faster edge rates into 50 Ω loads.

Key Specifications

Pinout & Package

Package: 8-pin 150-mil SOIC (Small Outline Integrated Circuit), surface-mount, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

Cypress CY2305CSXC-1HT has two functionally aligned alternatives with documented differences in drive strength, package, and temperature range.

Compared with IDT 85411AMLFT and ON Semi NB3N502DR2G, CY2305CSXC-1HT uniquely delivers zero-delay operation in an 8-pin SOIC with auto power-down and LVTTL-compatible outputs - making it optimal for space-constrained, low-power, phase-critical clock fanout applications.

Availability

CY2305CSXC-1HT is available at Aetrix Electronics and suitable for industrial PLC timing modules, FPGA clock distribution boards, and automotive infotainment head units requiring stable component supply, long-lifecycle support, and guaranteed commercial-temperature performance.

Supply support for CY2305CSXC-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) designs high-performance timing, memory, and microcontroller solutions for industrial, automotive, and communications markets.

The CY2305C product line delivers zero-delay clock fanout ICs optimized for deterministic timing in FPGA, ASIC, and microprocessor-based systems where inter-clock skew directly impacts functional correctness.

FAQ

What is the purpose of the CLKOUT pin in CY2305CSXC-1HT?

The CLKOUT pin provides internal feedback to the on-chip PLL and is essential for achieving zero input-to-output delay. Even if unused in the system, it must be loaded with the same capacitance as CLK1–CLK4 (e.g., 10–15 pF) to maintain phase alignment. Its voltage swing matches other outputs and it sources/sinks 12 mA like all buffered outputs.

Does CY2305CSXC-1HT require external configuration or programming?

No. CY2305CSXC-1HT is a fixed-function zero-delay buffer with no registers, I²C interface, or configuration pins. It operates autonomously upon power-up: the PLL locks to REF, and all five outputs become active after tPU (max 50 ms). No firmware, EEPROM, or external components are needed for basic operation.

Can CY2305CSXC-1HT drive 50 Ω transmission lines directly?

Yes - the –1H version provides 12 mA drive strength, supporting ≤1 ns rise/fall times into 50 Ω loads. However, proper impedance matching requires series termination at the source (e.g., 22–33 Ω resistor near the IC) and controlled trace impedance. Avoid unterminated 50 Ω routing to prevent reflections that degrade jitter and skew.

How does power-down mode activate and what happens to the outputs?

Power-down activates automatically when no rising edge occurs on REF for >100 µs. All outputs (CLK1–CLK4 and CLKOUT) are tri-stated, and supply current drops to <12 µA. Outputs remain inactive until the next REF rising edge, at which point the PLL relocks and outputs resume within one reference period - no reset pin or external control is needed.