Infineon Technologies CY7B9910-7SXCT

Overview

CY7B9910-7SXCT from Cypress Semiconductor is a low-skew, zero-delay clock buffer IC with eight TTL-compatible outputs, 15–80 MHz operation, <0.75 ns max output skew, and integrated PLL for precise system clock distribution in high-performance computing and telecom backplanes.

For engineers reviewing the CY7B9910-7SXCT datasheet, CY7B9910-7SXCT pinout, CY7B9910-7SXCT application, or CY7B9910-7SXCT equivalent, key selection criteria include output skew tolerance, PLL lock time (≤0.5 ms), FS-selectable frequency range, 50Ω transmission line drive capability, and TTL-level output swing (VOH ≥ 2.4 V at –40 mA).

Technical Context

The CY7B9910-7SXCT implements a fully integrated phase-locked loop with voltage-controlled oscillator (VCO), phase-frequency detector, and filter to achieve zero input-to-output delay and sub-nanosecond output alignment. Its feedback path accepts any of the eight Q outputs, enabling flexible tree-based clock distribution.

Three-level FS control pins select VCO operating bands (LOW/MID/HIGH) to support 15–30 MHz, 25–50 MHz, or 40–80 MHz nominal frequencies. The TEST pin enables test-mode bypass of the PLL for direct REF-to-output pass-through during validation.

Key Specifications

Pinout & Package

24-pin SOIC (300-mil width), surface-mount package with exposed pad not present; pin pitch 1.27 mm, body size 15.4 × 7.5 mm.

Key Features

Applications

Equivalent & Alternatives

Cypress CY7B9910-7SXCT has two functionally aligned alternatives with documented compatibility and trade-offs.

Compared with IDT 5V2310PGG and ON Semi NB3N502MNG, CY7B9910-7SXCT uniquely delivers 5 V TTL compatibility, eight matched outputs, and programmable 15–80 MHz operation in a single SOIC package - making it the only drop-in solution for legacy high-speed computing clock trees requiring zero-delay and sub-nanosecond skew.

Availability

CY7B9910-7SXCT is available at Aetrix Electronics and suitable for high-speed backplane clocking, PCI-X system timing, telecom line card synchronization, and industrial PLC real-time bus applications requiring stable component supply and long-term obsolescence management.

Supply support for CY7B9910-7SXCT 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, microcontrollers, and USB solutions for industrial, automotive, and communications markets.

The CY7B99xx family was designed specifically for low-skew, zero-delay clock distribution in high-performance computing and telecom infrastructure - addressing strict timing budgets in multi-GHz synchronous systems.

FAQ

What is the maximum supported clock frequency for CY7B9910-7SXCT?

The CY7B9910-7SXCT supports up to 80 MHz nominal output frequency when the FS pin is set HIGH. This is confirmed in the datasheet's Switching Characteristics table for the –7 speed grade (Page 6). Operation above 80 MHz violates AC timing limits and may cause PLL unlock or increased jitter beyond the specified 25 ps RMS.

Can CY7B9910-7SXCT drive unterminated 50Ω PCB traces?

No - the device is designed to drive 50Ω *terminated* transmission lines (to 2.06 V for TTL), as stated in the Functional Description and AC Test Load diagrams. Driving unterminated traces causes reflections, distorting edge rates and violating the 0.75 ns skew specification. External 50Ω parallel termination at the load is mandatory for compliance.

How does the TEST pin affect PLL behavior in normal operation?

In normal operation, the TEST pin must be held LOW (connected to GND) to enable full PLL functionality including zero-delay tracking and feedback-based frequency multiplication. If TEST floats or is pulled MID/HIGH, the PLL disconnects and outputs follow REF directly - resulting in uncontrolled jitter, no frequency multiplication, and loss of skew matching across devices.

Is CY7B9910-7SXCT pin-compatible with CY7B9920-7SXCT?

No - although both share identical pinouts and package, they differ electrically: CY7B9910-7SXCT provides TTL outputs (VOH ≥ 2.4 V), while CY7B9920-7SXCT provides CMOS outputs (VOH ≈ VCC). Swapping them risks logic threshold mismatch, excessive current draw, or failure to meet timing specs in TTL systems.