Infineon Technologies CY7B9911-5JCT

Overview

CY7B9911-5JCT from Cypress Semiconductor is a programmable skew clock buffer (PSCB) with eight TTL-compatible outputs arranged in four independently configurable pairs, supporting 3.75–100 MHz operation, <100 ps typical pair skew, zero input-to-output delay via integrated PLL, and selectable ±6 time-unit skew (up to ±18 ns at 100 MHz) for high-speed computer timing alignment.

For engineers reviewing the CY7B9911-5JCT datasheet, CY7B9911-5JCT pinout, CY7B9911-5JCT application, or CY7B9911-5JCT equivalent, key selection criteria include output skew tolerance, PLL-based zero-delay capability, three-level function select inputs (xF0/xF1), FS frequency range control, and 32-pin PLCC package compatibility with terminated 50 Ω transmission lines.

Technical Context

The CY7B9911-5JCT integrates a fully functional PLL with phase-frequency detector and loop filter to cancel external transmission line and load delays, enabling true zero input-to-output propagation delay. Its VCO and time unit generator produce discrete delay steps (tU = 1.0 ns at 100 MHz, scaling inversely with nominal frequency) controlled by the FS pin.

Each of four output pairs (1Q0/1Q1 through 4Q0/4Q1) is hardwired to one of nine skew/function configurations via dedicated three-level xF0/xF1 inputs, supporting divide-by-2, divide-by-4, inversion, and ±4tU skew - all simultaneously active across independent pairs without shared resource contention.

Key Specifications

Pinout & Package

32-pin Plastic Leaded Chip Carrier (PLCC) with 11.43 mm × 11.43 mm body, J-lead profile, and standard LCC footprint compatible with socketed and surface-mount assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar programmable skew clock buffer applications.

Compared with IDT5V9885BGI and ICS8302AM-01LFT, the CY7B9911-5JCT uniquely combines zero-delay PLL architecture, per-pair programmable skew up to ±18 ns, and on-chip ÷2/÷4 synthesis - making it the only option capable of closed-loop timing compensation in dynamically loaded TTL clock trees.

Availability

CY7B9911-5JCT is available at Aetrix Electronics and suitable for high-speed computer backplane timing, multi-ASIC synchronization, and industrial control system clock tree applications requiring stable component supply and long-term obsolescence management.

Supply support for CY7B9911-5JCT 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 programmable system-on-chip (PSoC), memory, and timing solutions for embedded and industrial markets.

The RoboClock+™ product line was designed specifically for high-performance clock distribution in computing and communications infrastructure, emphasizing programmable skew, zero-delay PLLs, and robust TTL interfacing for legacy and hybrid systems.

FAQ

What is the purpose of the FB pin on the CY7B9911-5JCT?

The FB (feedback) pin closes the internal PLL loop by connecting to one of the device's outputs-typically a zero-skew output (e.g., 1Q0 with xF0=xF1=MID). This allows the PLL to actively cancel transmission line and load delays, achieving true zero input-to-output propagation delay. Without a valid FB connection, the PLL remains unlocked and outputs default to REF-driven behavior with uncontrolled skew.

How does the FS pin affect timing performance?

The FS (frequency select) pin sets the VCO operating range and determines the time unit (tU) resolution: LOW (15–30 MHz, tU ≈ 1.0 ns), MID (25–50 MHz, tU ≈ 0.6 ns), or HIGH (40–100 MHz, tU ≈ 0.4 ns). Selecting the correct FS level ensures optimal tU granularity for target skew accuracy and guarantees stable PLL lock across the intended frequency band.

Can all eight outputs operate at different frequencies simultaneously?

Yes - each of the four output pairs (1Q0/1Q1 through 4Q0/4Q1) can be independently configured for ÷2, ÷4, non-inverted, or inverted operation using its dedicated xF0/xF1 inputs. For example, 1Q0/1Q1 may run at 100 MHz (undivided), while 2Q0/2Q1 runs at 50 MHz (÷2) and 3Q0/3Q1 at 25 MHz (÷4), all synchronized to the same REF input.

What happens if the TEST pin is left unconnected?

An unconnected TEST pin defaults to MID level (VCC/2) due to internal termination, which disables the PLL and forces all outputs to follow the REF waveform directly - bypassing skew programming and frequency synthesis. To ensure normal operation, TEST must be tied LOW (GND); floating or MID states result in loss of zero-delay functionality and undefined skew behavior.