Infineon Technologies CY7B9950AXI

Overview

CY7B9950AXI from Cypress Semiconductor is a 2.5/3.3 V, 200 MHz multi-phase PLL clock buffer with eight LVTTL outputs, programmable phase skew (±7.5 ns in 625/1250 ps steps), and split-output-bank power supplies (VDDQ1–VDDQ4). It serves as a high-precision clock distribution IC in high-speed computing and telecom clock trees, delivering 50 ps typical output-output skew and 50 ps cycle-cycle jitter.

For engineers reviewing the CY7B9950AXI datasheet, CY7B9950AXI pinout, CY7B9950AXI application, or CY7B9950AXI equivalent, key selection criteria include its dual-voltage bank operation, selectable edge synchronization (rising/falling), 2×/4× multiply and 1/2×/1/4× divide ratios, spread-spectrum compatibility, and industrial temperature range (–40 °C to +85 °C).

Technical Context

The CY7B9950AXI integrates a voltage-controlled oscillator (VCO) with frequency-selectable operating ranges (24–50 MHz, 48–100 MHz, or 96–200 MHz via FS pin), enabling precise PLL lock across diverse reference frequencies. Its four independent output banks (1Qn–4Qn) support per-bank divider settings (K/M), phase offsets, and drive strength control via three-level PE/HD.

Phase adjustment uses discrete time-unit increments (tU = 1/(f_NOM × MF)), where MF scales with FS level (32/16/8), yielding 625 ps or 1250 ps resolution. Feedback routing from any output (e.g., 2Q0/2Q1) allows zero-delay configuration and flexible multiplication/division topologies without external components.

Key Specifications

Pinout & Package

Package: 32-pin TQFP (7 mm × 7 mm, 0.8 mm pitch), RoHS-compliant, moisture sensitivity level 3.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multi-phase PLL clock buffer applications.

Compared with IDT5V9885BPGI and NB3N502FG, the CY7B9950AXI uniquely combines eight outputs, split VDDQ domains, ±7.5 ns programmable skew, and PLL feedback reconfiguration - making it the only option for high-density, mixed-voltage, phase-critical clock trees.

Availability

CY7B9950AXI is available at Aetrix Electronics and suitable for high-speed memory subsystems, telecom line card timing, industrial PLC backplane clocking, and test equipment signal generation requiring stable component supply and long-term industrial lifecycle support.

Supply support for CY7B9950AXI 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 fabless semiconductor company specializing in high-performance timing, memory, and programmable logic solutions for industrial, automotive, and communications markets.

The RoboClock® product line delivers programmable, low-jitter clock distribution ICs optimized for phase-sensitive applications in servers, routers, and real-time control systems - emphasizing skew control, mixed-voltage operation, and PLL configurability.

FAQ

What is the function of the TEST pin on CY7B9950AXI?

The TEST pin is a three-level input that disables the PLL when held at MID or HIGH, routing the REF signal directly to Banks 1–2 and through dividers K/M to Banks 3–4. In normal operation, TEST must be held LOW to enable PLL functionality and maintain phase lock across all outputs.

Can CY7B9950AXI generate a 100 MHz output from a 25 MHz reference?

Yes - by setting FS = M (48–100 MHz VCO range) and configuring feedback from an output (e.g., 2Q0) to FB, the internal PLL multiplies the 25 MHz reference by 4× to produce 100 MHz outputs across all banks, with phase alignment preserved via the nF[1:0] controls.

How does the PE/HD pin affect output timing behavior?

PE/HD selects both edge synchronization and drive strength: LOW synchronizes outputs to the falling edge of REF with ±12 mA drive; MID enables rising-edge sync and ±24 mA drive; HIGH enables rising-edge sync with ±12 mA drive - critical for matching setup/hold timing in source-synchronous interfaces.

Is external termination required for CY7B9950AXI's LVTTL outputs?

No - the device drives 50 Ω terminated lines directly. Its output buffers are designed for LVTTL levels into 50 Ω loads, with VOL ≤ 0.4 V and VOH ≥ 2.0 V (2.5 V supply) or ≥ 2.4 V (3.3 V supply) under specified IOL/IOH conditions, eliminating need for series resistors or external terminations.