NXP Semiconductors MPC9992FA

Overview

MPC9992FA from Freescale Semiconductor is a 3.3 V differential ECL/PECL PLL clock generator with SiGe technology, delivering 7 differential PECL outputs, sub-100 ps output skew, and output frequencies up to 400 MHz. It supports dual-frequency bank generation (QA[3:0], QB[2:0]), crystal or differential PECL reference input, and SYNC pulse generation for non-binary frequency alignment-used in high-end workstation and telecom timing systems.

For engineers reviewing the MPC9992FA datasheet, MPC9992FA pinout, MPC9992FA application, or MPC9992FA equivalent, this page provides verified technical context on PLL configuration modes, VCO feedback dividers, LVCMOS control interface, PECL output drive capability into 50 Ω loads, and thermal design guidance for VCC_PLL filtering.

Technical Context

The MPC9992FA implements a fully differential SiGe PLL with programmable VCO feedback dividers (M = 32–160) and selectable VCO scaling (÷2 or ÷4 via VCO_SEL), enabling reference input frequencies from 5 MHz to 50 MHz across eight distinct PLL configurations. Output banks QA and QB are independently configurable with frequency ratios of 2:1, 3:1, 3:2, or 5:2 relative to each other.

It integrates a dedicated SYNC pulse generator that detects coincident edges between QA and QB banks, producing a single-cycle logic-high pulse synchronized to QA period-critical for system-level timing coordination where integer-ratio clocks are insufficient. All control inputs (FSEL[1:0], REF_SEL, PLL_EN, MR/STOP, VCO_SEL) are LVCMOS-compatible, while PCLK/PCLK and all outputs operate at PECL levels with internal 50 Ω termination support.

Key Specifications

Pinout & Package

Package: 32-lead LQFP (Case 873A-04), lead-free compatible, 0°C to +70°C ambient operating range.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PLL-based differential clock generation applications.

Compared with MPC9992FA, IDT5V9885BGI offers software configurability at the cost of added system complexity, while NB3N502FG reduces pin count and BOM cost but sacrifices ratio flexibility and SYNC functionality-making MPC9992FA optimal for fixed-function, high-synchronization-demand systems.

Availability

MPC9992FA is available at Aetrix Electronics and suitable for workstation backplane timing, telecom line card clocking, and mainframe memory interface applications requiring stable component supply, long-lifecycle availability, and consistent electrical performance across production batches.

Supply support for MPC9992FA 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

Freescale Semiconductor (now part of NXP Semiconductors) was a leading designer of high-performance analog and mixed-signal ICs for computing, networking, and industrial infrastructure.

The MPC9992FA belongs to Freescale's Advanced Clock Drivers product line, engineered specifically for low-skew, low-jitter clock distribution in high-end computing and telecom systems where deterministic timing alignment is critical.

FAQ

What is the maximum output frequency supported by the MPC9992FA?

The MPC9992FA supports output frequencies up to 400 MHz in ÷4 mode (e.g., VCO = 1600 MHz ÷ 4). This maximum applies to QA[3:0] outputs under PLL-locked conditions with appropriate VCO_SEL and FSEL[1:0] settings. The device achieves this using SiGe process technology and fully differential signaling to maintain signal integrity at high frequencies.

Does the MPC9992FA require an external loop filter?

No, the MPC9992FA does not require an external loop filter. Its PLL is fully integrated with on-die components optimized for 3.3 V operation. This simplifies PCB layout and reduces bill-of-materials count. However, proper decoupling and VCC_PLL filtering (10–15 Ω + 22 µF) remain essential to suppress power supply noise that degrades jitter performance.

How is the SYNC pulse generated on the MPC9992FA?

The MPC9992FA generates the QSYNC pulse by monitoring phase relationships between QA[3:0] and QB[2:0] output banks. When edges coincide, it asserts a single-cycle logic-high pulse synchronized to the QA period. This occurs automatically in all eight PLL configurations-no registers or software control are involved. The pulse width is QA period ±5%, and placement depends strictly on the programmed frequency ratio.

Can the MPC9992FA operate with both crystal and differential clock inputs?

Yes, the MPC9992FA supports both reference sources. The REF_SEL pin selects between differential PECL input (PCLK/PCLK) and crystal oscillator interface (XTAL_IN/XTAL_OUT). When REF_SEL = 1, PCLK drives the PLL; when REF_SEL = 0, the crystal provides the reference. Both paths feed the same phase detector, ensuring identical jitter transfer characteristics regardless of source.

What is the purpose of the VCC_PLL pin on the MPC9992FA?

The VCC_PLL pin supplies power exclusively to the analog PLL circuitry-including the VCO, phase detector, and charge pump-separating it from digital output buffers powered by VCC. This isolation minimizes switching noise coupling into sensitive analog blocks. Because VCC_PLL current draw is up to 12 mA, a dedicated RC filter (10–15 Ω + 22 µF) is mandatory to maintain voltage stability and prevent jitter degradation.